CN116759133A - Conductive silver aluminum paste, preparation method, electrode and N-type Topcon battery - Google Patents

Abstract

The invention discloses a conductive silver aluminum paste, a preparation method, an electrode and an N-type Topcon battery. The conductive silver aluminum paste contains silver powder, aluminum powder, inorganic powder additives, glass powder and organic carrier. The total weight of the conductive silver aluminum paste is 100 In terms of %, the weight percentage of each component is: silver powder 80.0% ~ 90.0%; aluminum powder 0.5% ~ 3.0%; inorganic powder additive 0.0% ~ 1.0%; glass powder 1.0% ~ 6.0%; organic carrier 7.0% ~ 13.0%; wherein, the particle size distribution range of the silver powder is 0.1-4.5 μm, and the D50 distribution range is 0.8-2.0 μm; the particle size distribution range of the aluminum powder is 0.3-5.0 μm, and the D50 distribution range is 0.8-2.0 μm; the glass powder includes a first glass powder and/or a second glass powder, and the first glass powder is Pb-Zn-Si-Ga-B-Li-O system, Pb-Zn-Si-Al-B -Li-O system or one or more of the two composite structures Pb-Zn-Si-Ga-Al-B-Li-O glass powder, and the second glass powder is Pb-Si-Ti-B- Se-O system glass powder, the particle size distribution range of the glass powder is 0.1-8.0 μm, and the D50 distribution range is 0.5-2.0 μm. The invention realizes that the gate line of the N-type Topcon type silicon solar cell has high reliability and strong acid and corrosion resistance.

Description

Conductive silver aluminum paste, preparation method, electrode and N-type Topcon battery

Technical field

The invention belongs to the field of silicon solar cells, and in particular relates to a conductive silver aluminum paste, a preparation method, an electrode and an N-type Topcon battery.

Background technique

Solar energy is currently the energy source with the largest reserves and the most widespread distribution in the world. It is the best choice to replace fossil energy. Therefore, the development and utilization of solar energy has become a hot spot for various countries to compete for development. It can be converted into thermal energy, biological energy, electrical energy, etc. for human use. As a result, many solar energy use projects have been developed, among which silicon solar cell power generation projects are one of the most important development projects currently.

Silicon solar cells mainly consist of front electrode, anti-reflection layer, PN junction, silicon substrate, and back field. When light irradiates the surface of the solar cell, it is fully absorbed by the surface anti-reflection layer, and the photons enter the PN junction. The photons are absorbed by the PN junction, and a photoelectric effect occurs inside the PN junction, thereby releasing electrons. The electrons are derived from the surface electrons to form a current. , that is, converting light energy into electrical energy. With the development and progress of silicon solar cell technology, high-efficiency N-type Topcon cells have gradually become the mainstream of silicon solar cell development. Theoretically, N-type semiconductor Topcon batteries have the characteristics of long minority carrier lifetime and weak light-induced attenuation. N-type Top-con batteries have high open circuit voltage, high photoelectric conversion efficiency, and high output power. In order to actually develop high-efficiency N-type top-con batteries, two major problems need to be solved. One is the cell structure design and process, and the other is the development of silver-aluminum paste to metallize the surface of the battery.

Among them, the surface metallized silver aluminum paste of the battery developed is the same as the silver paste used for P-type Se-Perc cells. The service life and anti-aging effect of the battery components will become an important restriction restricting the use of silver aluminum paste. Silicon solar power generation equipment is an electronic device that combines numerous cells in series or parallel and then packages them. The materials currently used for solar cell packaging contain certain organic substances, such as EVA. These substances will produce acids, such as acetic acid, under long-term light exposure. These substances will corrode the surface electrodes of silicon solar cells, leading to problems such as electrode peeling and poor contact. , reducing the photoelectric conversion efficiency of silicon solar cells and seriously affecting the service life of silicon solar cells.

Contents of the invention

The purpose of the present invention is to provide a conductive silver aluminum paste, preparation method, electrode and N-type Topcon battery, by improving the stability, burning effect, acid corrosion resistance of glass powder, and controlling the corrosion effect of glass on battery sheets , which improves the acid corrosion resistance of the conductive silver aluminum paste of silicon solar cells, and the N-type Top-con silicon solar cell front electrode prepared by using this silver aluminum paste. The electrode has good acid and corrosion resistance, high opening voltage and low contact resistance. Low, high photoelectric conversion efficiency and long battery life. In order to achieve the above objects, the technical solutions adopted by the present invention are:

The invention provides a conductive silver aluminum paste. The conductive silver aluminum paste contains silver powder, aluminum powder, inorganic powder additives, glass powder and organic carrier. Based on the total weight of the conductive silver aluminum paste being 100%, each component The weight percentage is:

Wherein, the particle size distribution range of the silver powder is 0.1-4.5 μm, and the D50 distribution range is 0.8-2.0 μm; the particle size distribution range of the aluminum powder is 0.3-5.0 μm, and the D50 distribution range is 0.8-2.0 μm; The glass powder includes a first glass powder and/or a second glass powder, and the first glass powder is Pb-Zn-Si-Ga-B-Li-O system, Pb-Zn-Si-Al-B-Li- O system or one or more of the two composite structures Pb-Zn-Si-Ga-Al-B-Li-O glass powder, the second glass powder is Pb-Si-Ti-B-Se-O System glass powder, the particle size distribution range of the glass powder is 0.1-8.0 μm, and the D50 distribution range is 0.5-2.0 μm.

Further, in the first glass powder, based on the total mole number of each component included in the first glass powder being 100%, the corresponding mole percentage of each component is as follows:

Further, the first modified additive is an oxide of one or more elements among Ca, Sr, Ba, Na, Ti, Zr, Sb, Ge, Sn, In, and Tl, or is made into The first glass powder is decomposed to obtain the oxide of the element.

Further, in the second glass powder, based on the total mole number of each component included in the second glass powder being 100%, the corresponding mole percentage of each component is as follows:

Further, the second modification additive is an oxide of one or more elements among Zn, Ca, Sr, Ba, Li, Na, Al, Zr, Sb, Ge, Sn, Ga, In, and Tl. , or a substance that decomposes to obtain the oxide of the element during the process of making the second glass powder.

Further, the inorganic powder additive is one or more of boron powder, silicon powder, silicon nitride powder, boron nitride powder, and silicon boride powder, and the particle size distribution range of the inorganic powder additive is 0.1 ~8.0μm, D50 distribution range is 0.5~2.0μm.

Further, the organic carrier includes organic solvent, organic resin, and additives. Based on the total weight of the organic carrier being 100%, the content of each component is as follows:

Organic solvent 60.0% ~ 85.0%;

Organic resin 5.0% ~ 30.0%;

Additive 2.0%～15.0%.

Further, the organic solvent is diethylene glycol butyl ether acetate, diethylene glycol ethyl ether acetate, alcohol ester 12, dimethyl phthalate, ethylene glycol butyl ether benzoate, tripropylene glycol mono One or more of methyl ether, diethylene glycol butyl ether, and pentaerythritol triacrylate.

Further, the organic resin is SEPS resin, SEBS resin, polyvinyl butyral resin, poly-α-methylstyrene resin, petroleum resin, acrylic resin, cellulose acetate butyrate, carboxymethyl cellulose, hydroxyl One or more types of ethylcellulose.

Further, the additive is one or more of silicone oil, palmitic acid, lithium stearate, polyamide wax, and hydrogenated castor oil.

The present invention also provides a method for preparing the above-mentioned conductive silver aluminum paste, which includes the following steps:

Preparation of glass powder: The raw materials used for glass powder are weighed according to the set ratio, mixed, and then melted at high temperature, cooled and dried, and then crushed to obtain the required glass powder;

Preparing the organic carrier: Weigh the raw materials used for the organic carrier according to the set ratio, heat, stir and mix, centrifuge at high speed to disperse evenly, and then filter to obtain the required organic carrier;

Preparation of conductive silver-aluminum paste: Add silver powder, aluminum powder, inorganic powder additives, and prepared glass powder to the prepared organic carrier according to mass proportions, mix and stir evenly, and then grind, adjust and filter to obtain Required conductive silver aluminum paste.

The present invention also provides an electrode, which is sintered on the surface of the battery silicon wafer through the above-mentioned conductive silver aluminum paste.

The present invention also provides an N-type Topcon battery, including the above-mentioned electrode.

To sum up, the conductive silver aluminum paste of the present invention uses the first glass powder and/or the second glass powder, both of which are high lead-containing glasses. The glass softening point is lower, the corrosion resistance is better, and it has better corrosion resistance. The liquid phase assists the firing effect. When the silver-aluminum paste is sintered, the glass liquid can properly corrode the insulating film on the battery surface, and has better open circuit voltage and contact resistance.

The first glass powder uses a higher content of Si, Ga, Al and other elements, and reduces the content of B and alkali metal Li, which improves the stability of the glass structure and reduces the degree of hydrolysis of the glass, thus reducing the silver grid lines. The degree of corrosion increases the anti-aging strength of the silver grid lines; the second glass powder introduces the Se element to lower the softening point of the glass, which can promote the high lead glass to be able to melt into a larger amount even with extremely low alkali metal content. Si and Ti element oxides, Si and Ti and other elements have stable structures. The introduced oxides of corresponding elements are difficult to corrode and hydrolyze, which improves the stability of high-lead glass and the stability of precipitated crystals, while maintaining the glass's better The firing effect effectively improves the density of the silver grid lines formed after the sintering of the silver-aluminum paste, reduces the corrosion degree of the silver grid lines formed after the sintering of the silver-aluminum paste, and improves the anti-aging strength of the silver grid lines.

Thus, the present invention realizes an N-type Topcon type silicon solar cell silver-aluminum paste with high grid line reliability, good corrosion resistance, strong anti-aging ability, high opening voltage, low contact resistance and high photoelectric conversion efficiency.

Detailed ways

The invention provides a conductive silver aluminum paste. The conductive silver aluminum paste contains silver powder, aluminum powder, inorganic powder additives, glass powder and organic carrier. Based on the total weight of the conductive silver aluminum paste being 100%, the weight percentage of each component The content is:

Among them, the silver powder is spherical or quasi-spherical, with a particle size distribution range of 0.1 to 4.5 μm, and a D50 distribution range of 0.8 to 2.0 μm; aluminum powder. Aluminum powder is spherical or quasi-spherical, with a particle size distribution range of 0.3 to 5.0 μm. , D50 distribution range is 0.8~2.0μm; the glass powder includes the first glass powder and/or the second glass powder, the first glass powder is Pb-Zn-Si-Ga-B-Li-O system, Pb-Zn-Si -One or more of the Al-B-Li-O system or their composite structure Pb-Zn-Si-Ga-Al-B-Li-O glass powder, the second glass powder is Pb-Si-Ti- B-Se-O system glass powder, the glass powder is spherical or quasi-spherical, the particle size distribution range is 0.1~8.0μm, and the D50 distribution range is 0.5~2.0μm.

Further, in the above-mentioned conductive silver aluminum paste, the first glass powder contains the first modifying additive. Based on the total mole number of the first glass powder containing each component being 100%, the corresponding mole percentages of each component are as follows:

Wherein, the first modified additive is an oxide of one or more elements among Ca, Sr, Ba, Na, Ti, Zr, Sb, Ge, Sn, In, Tl, or the first glass powder is made into A substance that decomposes during the process to obtain an oxide of that element. Substances that decompose to obtain oxides of the corresponding elements can be carbonates, peroxides or complexes.

Similarly, components such as PbO, ZnO, SiO ₂ , Ga ₂ O ₃ , Al ₂ O ₃ , B ₂ O ₃ , and Li ₂ O in the first glass powder can be oxides added directly, or they can be added during the production of the first glass powder. During the glass powder process, substances with the above components are decomposed, such as carbonates, peroxides or compounds.

Further, in the second glass powder, based on the total mole number of each component included in the second glass powder being 100%, the corresponding mole percentage of each component is as follows:

Wherein, the second modification additive is an oxide of one or more elements among Zn, Ca, Sr, Ba, Li, Na, Al, Zr, Sb, Ge, Sn, Ga, In, Tl, or The substance that is decomposed to obtain the oxide of the element during the process of making the second glass powder. Substances that decompose to obtain oxides of the corresponding elements can be carbonates, peroxides or complexes.

Similarly, components such as PbO, SiO ₂ , TiO ₂ , B ₂ O ₃ , and SeO ₂ in the second glass powder can be directly added oxides, or they can be decomposed during the process of making the second glass powder to obtain the above components. , such as carbonates, peroxides or compounds.

Further, the above-mentioned inorganic powder additive is one or more of boron powder, silicon powder, silicon nitride powder, boron nitride powder, and silicon boride powder, and the particle size distribution range of the inorganic powder additive is 0.1 to 8.0 μm, D50 distribution range is 0.5~2.0μm.

Further, the above-mentioned organic carrier includes organic solvent, organic resin, and additives. Based on the total weight of the organic carrier being 100%, the content of each component is as follows:

Organic solvent 60.0% ~ 85.0%;

Organic resin 5.0% ~ 30.0%;

Additive 2.0%～15.0%.

Among them, the organic solvents are diethylene glycol butyl ether acetate, diethylene glycol ethyl ether acetate, alcohol ester 12, dimethyl phthalate, ethylene glycol butyl ether benzoate, tripropylene glycol monomethyl ether, One or more of diethylene glycol butyl ether and pentaerythritol triacrylate; the organic resin is SEPS resin, SEBS resin, polyvinyl butyral resin, polyα-methylstyrene resin, petroleum resin, acrylic resin , one or more of cellulose acetate butyrate, carboxymethyl cellulose, and hydroxyethyl cellulose; the additive is one or more of silicone oil, palmitic acid, lithium stearate, polyamide wax, hydrogenated castor oil, or There are many kinds of silicone oil, preferably dimethyl silicone oil.

The invention also provides a method for preparing the above-mentioned conductive silver aluminum paste, which includes the following steps:

Preparing glass powder: Weigh the glass powder precursor raw materials according to the set ratio, mix them evenly through ball milling or sieving, and place them in a crucible. Then put the crucible into a high-temperature furnace and melt at 850°C ~ 1100°C for 10 minutes ~ 60 minutes, after melting evenly, pour the glass liquid into cold water of 5℃~20℃ for rapid cooling and cooling to obtain glass particles. After drying, the glass particles are preliminarily pulverized, and then finely pulverized to obtain suitable particle size. Required glass powder;

Preparing the organic carrier: Weigh the raw materials of the organic carrier using organic solvent, organic resin, and additives according to the set ratio, then heat and stir in a water bath at 70°C to 100°C to mix evenly, and then disperse evenly through high-speed centrifugation and then filter to obtain the resultant. Requires organic carrier;

Prepare conductive silver aluminum paste: Add the prepared silver powder, aluminum powder, inorganic powder additive, glass powder, and organic carrier to the prepared organic carrier in mass proportions, mix and stir evenly, and then grind through three rollers. After adjusting the viscosity and finally filtering, the required conductive silver aluminum paste is obtained.

The invention also provides an electrode, which is sintered on the surface of the battery silicon wafer through the above-mentioned conductive silver aluminum paste. Specifically, the prepared conductive silver aluminum paste is printed by screen printing to form the required grid lines on the surface of the N-type Topcon battery, and then sintered to form a conductive silver grid electrode. For other technical features of the electrode, please refer to the prior art, which will not be described again here.

The present invention also provides an N-type Topcon battery, including the above-mentioned electrodes. For other technical features of the N-type Topcon battery, please refer to the prior art, which will not be described again here.

The beneficial effects of the present invention are as follows:

The conductive silver aluminum paste of the present invention uses the first glass powder and/or the second glass powder, both of which are high lead-containing glasses. The glass softening point is lower, the corrosiveness is better, and the liquid phase assisting effect is better. , when the silver-aluminum paste is sintered, the glass liquid can properly corrode the insulating film on the battery surface, and has better open circuit voltage and contact resistance. The first glass powder uses a higher content of Si, Ga, Al and other elements, and reduces the content of B and alkali metal Li, which improves the stability of the glass structure and reduces the degree of hydrolysis of the glass, thus reducing the silver grid lines. The degree of corrosion increases the anti-aging strength of the silver grid lines; the second glass powder introduces the Se element to lower the softening point of the glass, which can promote the high lead glass to be able to melt into a larger amount even with extremely low alkali metal content. Si and Ti element oxides, Si and Ti and other elements have stable structures. The introduced oxides of corresponding elements are difficult to corrode and hydrolyze, which improves the stability of high-lead glass and the stability of precipitated crystals, while maintaining the glass's better The firing effect effectively improves the density of the silver grid lines formed after the sintering of the silver-aluminum paste, reduces the corrosion degree of the silver grid lines formed after the sintering of the silver-aluminum paste, and improves the anti-aging strength of the silver grid lines.

The present invention will be described in further detail below in conjunction with test examples and specific implementations. However, this should not be understood to mean that the scope of the above-mentioned subject matter of the present invention is limited to the following embodiments. All technologies implemented based on the contents of the present invention belong to the scope of the present invention.

The following is explained in conjunction with specific embodiments:

Examples BG1-BG6:

Preparation of the first glass powder: Calculate and weigh the raw materials of the first glass powder according to the set formula, then mix them evenly through ball milling or sieving, then place them in a crucible, and then put the crucible into a high-temperature furnace at 850°C. Melt at ~1100℃ for 10min~60min. After the melting is even, pour the glass liquid into cold water at 5℃~20℃ for rapid cooling and cooling to obtain glass particles. After drying, the glass particles are initially crushed, and then Finely pulverize to obtain the required glass powder with suitable particle size, wherein the first glass powder is numbered BG1-BG6, and the specific composition molar ratio of the first glass powder is as shown in Table 1.

Table 1 First glass powder mole percentage table (at%)

Examples BS1-BS6:

Preparation of the second glass powder: Calculate and weigh the raw materials of the second glass powder according to the set formula, then mix them evenly through ball milling or sieving, then place them in a crucible, and then put the crucible into a high-temperature furnace at 850°C. Melt at ~1100℃ for 10min~60min. After the melting is even, pour the glass liquid into cold water at 5℃~20℃ for rapid cooling and cooling to obtain glass particles. After drying, the glass particles are initially crushed, and then Finely pulverize to obtain the required glass powder with suitable particle size, wherein the second glass powder is numbered BS1-BS6, and the specific molar ratio of the second glass powder is as shown in Table 2.

Table 2 Second glass powder composition table (at%)

Examples ZT1-ZT6:

Preparation of the organic carrier: Weigh the raw materials of the organic carrier using organic solvent, organic resin, and additives according to the set ratio, then heat and stir in a water bath at 70°C to 100°C to mix evenly, and then disperse evenly through high-speed centrifugation and then filter to obtain The required organic carriers are numbered ZT1-ZT6 and are available for use. The mass composition ratio of each organic carrier is as shown in Table 3.

Table 3 Organic carrier weight component list (wt%)

Examples AA01-AA15:

Preparation of conductive silver aluminum paste: number the silver powder as AG1, the aluminum powder as AL1, and number the inorganic powder additives boron powder, silicon powder, silicon nitride powder, boron nitride powder, and silicon boride powder with appropriate particle sizes in sequence. For TJ1, TJ2, TJ3, TJ4, and TJ5, according to the material combination selected in Table 4 and the mass percentage provided, weigh the corresponding silver powder, aluminum powder, inorganic powder additives, and glass powder respectively, and add them to the corresponding model and mass In the organic carrier, mix it evenly, then use a three-roller mill to grind it and then filter it to obtain a rough slurry. After mixing, conductive silver aluminum slurry AA01-AA15 is obtained. The specific weight composition of the silver aluminum slurry is as shown in Table 4. shown.

Table 4 Silver aluminum paste weight composition table (wt%)

Continued Table 4 Weight composition table of silver aluminum paste (wt%)

Test example:

The silver aluminum paste prepared in the above examples AA01-AA15 was screen-printed on the N-type Topcon battery sheet onto the battery surface, and then dried, sintered and cooled to obtain a battery containing printed silver grid electrodes. The resulting battery was subjected to Efficiency test, and exposing the prepared silicon solar cells to a sealed environment of 3% potassium acetate chloride saturated solution at 85°C, using a fan to circulate the air in the sealed environment for 10 hours, then turn off the fan After cooling the sealed environment to room temperature, take out the silicon solar cells, test the photoelectric conversion efficiency of the cells after the experiment, compare the difference in photoelectric conversion efficiency of the cells before and after, and calculate the attenuation percentage of the photoelectric conversion efficiency of these cells. In order to facilitate the observation of the electrical performance characteristics of the silver-aluminum paste of the present invention, the silver-aluminum paste 995PFB produced by Shanghai Silver Paste Technology Co., Ltd. was selected for printing, sintering and testing under the same conditions to compare the electrical properties with the silver-aluminum paste of the present invention. The test results are shown in the table 5.

Table 5 Test data table of silver aluminum paste of the present invention

As can be seen from Table 5, comparing the embodiments AA01-AA15 of the present invention and the silver-aluminum paste 995PFB silver-aluminum paste produced by Shanghai Silver Paste Technology Co., Ltd., it is found that the open-circuit voltage of the silver-aluminum paste battery of the present invention is higher, the contact resistance is lower, and the photovoltaic The conversion efficiency is high, and the photoelectric conversion efficiency in the potassium acetate chloride experiment has a low attenuation rate. It can be seen from Table 5 that the open circuit voltage of each embodiment of the present invention is ≥0.7181V, the series resistance is ≤0.261mΩ, the photoelectric conversion efficiency is ≥25.13%, and the photoelectric conversion efficiency attenuation rate of the potassium acetate chloride experiment is ≤13.02%, which is far from Less than 58.03% of the comparative example, this shows that the silver-aluminum paste provided by the present invention has good contact effect, high open circuit voltage, high photoelectric conversion efficiency, low attenuation rate of photoelectric conversion efficiency in the potassium acetate chloride experiment, good acid resistance and corrosion resistance, and good resistance to acid and corrosion. Strong aging ability.

It should be noted that each embodiment in this specification is described in a progressive manner. Each embodiment focuses on its differences from other embodiments. The same and similar parts between the various embodiments are referred to each other. Can.

The above are only specific embodiments of the present invention, but the protection scope of the present invention is not limited thereto. Any person familiar with the technical field can easily think of changes or substitutions within the technical scope disclosed in the present invention. All are covered by the protection scope of the present invention. Therefore, the scope of protection of the present invention should be determined by the appended claims.

Claims (13)

1. The conductive silver-aluminum paste is characterized by comprising silver powder, aluminum powder, inorganic powder additives, glass powder and an organic carrier, wherein the total weight of the conductive silver-aluminum paste is 100%, and the conductive silver-aluminum paste comprises the following components in percentage by weight:

wherein the grain size distribution range of the silver powder is 0.1-4.5 mu m, and the D50 distribution range is 0.8-2.0 mu m; the grain size distribution range of the aluminum powder is 0.3-5.0 mu m, and the D50 distribution range is 0.8-2.0 mu m; the glass powder comprises a first glass powder and/or a second glass powder, wherein the first glass powder is one or more of Pb-Zn-Si-Ga-B-Li-O system, pb-Zn-Si-Al-B-Li-O system or Pb-Zn-Si-Ga-Al-B-Li-O system with a composite structure, the second glass powder is Pb-Si-Ti-B-Se-O system glass powder, the particle size distribution range of the glass powder is 0.1-8.0 mu m, and the D50 distribution range is 0.5-2.0 mu m.

2. The conductive silver aluminum paste of claim 1, wherein in the first glass frit, the corresponding mole percentages of the components are as follows, based on the total number of moles of the components contained in the first glass frit as 100%:

3. the conductive silver aluminum paste of claim 2, wherein the first modifying additive is an oxide of one or more elements of Ca, sr, ba, na, ti, zr, sb, ge, sn, in, tl or a material that decomposes to obtain the oxide of the element during the process of making the first glass frit.

4. The conductive silver aluminum paste of claim 1, wherein in the second glass frit, the corresponding mole percentages of the components are as follows, based on the total number of moles of the components contained in the second glass frit as 100%:

5. the conductive silver aluminum paste of claim 4, wherein the second modifying additive is an oxide of one or more elements of Zn, ca, sr, ba, li, na, al, zr, sb, ge, sn, ga, in, tl or a material that decomposes to provide an oxide of the element during the formation of the second glass frit.

6. The conductive silver-aluminum paste according to claim 1, wherein the inorganic powder additive is one or more of boron powder, silicon nitride powder, boron nitride powder and silicon boride powder, the particle size distribution range of the inorganic powder additive is 0.1-8.0 μm, and the D50 distribution range is 0.5-2.0 μm.

7. The conductive silver-aluminum paste according to claim 1, wherein the organic carrier comprises an organic solvent, an organic resin and an additive, and the contents of the components are as follows, based on the total weight of the organic carrier as 100 percent:

60.0 to 85.0 percent of organic solvent;

5.0 to 30.0 percent of organic resin;

2.0 to 15.0 percent of additive.

8. The conductive silver aluminum paste of claim 7, wherein the organic solvent is one or more of diethylene glycol butyl ether acetate, diethylene glycol diethyl ether acetate, alcohol ester twelve, dimethyl phthalate, ethylene glycol butyl benzoate, tripropylene glycol monomethyl ether, diethylene glycol butyl ether, pentaerythritol triacrylate.

9. The conductive silver aluminum paste of claim 7, wherein the organic resin is one or more of SEPS resin, SEBS resin, polyvinyl butyral resin, poly-alpha-methyl styrene resin, petroleum resin, acrylic resin, cellulose acetate butyrate, carboxymethyl cellulose, hydroxyethyl cellulose.

10. The conductive silver aluminum paste of claim 7, wherein the additive is one or more of silicone oil, palmitic acid, lithium stearate, polyamide wax, hydrogenated castor oil.

11. A method for preparing the conductive silver-aluminum paste according to any of the preceding claims 1 to 10, characterized by comprising the following steps:

preparing glass powder: weighing raw materials used for the glass powder according to a set proportion, mixing, melting at high temperature, cooling, drying, and crushing to obtain the required glass powder;

preparing an organic carrier: weighing raw materials used for the organic carrier according to a set proportion, heating, stirring, mixing, high-speed centrifuging, dispersing uniformly, and filtering to obtain the required organic carrier;

preparing conductive silver-aluminum paste: adding silver powder, aluminum powder, inorganic powder additives and prepared glass powder into prepared organic carriers respectively according to mass ratio, mixing and stirring uniformly, and grinding, viscosity adjusting and filtering to obtain the required conductive silver-aluminum paste.

12. An electrode, characterized in that the electrode is formed by sintering the conductive silver-aluminum paste according to any one of claims 1-10 on the surface of a battery silicon wafer.

13. An N-type Topcon cell comprising the electrode of claim 12.