An organic carrier for a conductive paste of a solar cell, a preparation method and an application

Abstract

This application belongs to the field of crystalline silicon solar energy technology. This application discloses an organic carrier for a solar cell conductive paste, a preparation method, and an application. The raw materials of the organic carrier for the solar cell conductive paste in this application include an elastomer, a thickening agent, an organic solvent, and an auxiliary agent; the elastomer is a PaMS resin; the auxiliary agent includes a dispersing agent and a second surfactant. The preparation method of the organic carrier for the solar cell conductive paste in this application is: mixing the raw materials and heating, and then obtaining the organic carrier after cooling. The organic carrier prepared in this application is applied in the solar cell conductive paste. The organic carrier prepared in this application has good stability and dispersibility after being mixed with the conductive paste, effectively solves the problem of the printing durability of the conductive paste, and can maintain the stable photoelectric conversion efficiency of the solar cell wafer.

Description

Technical Field

[0001] This application relates to the technical field of crystalline silicon solar energy, and particularly relates to an organic carrier for a conductive paste of a solar cell, a preparation method, and an application thereof. Background Art

[0002] Crystalline silicon solar cells are the mainstream technology in photovoltaic power generation technology. Photovoltaic cells use silicon materials as the substrate and cannot directly lead out the current in a way of contacting wires for use. Therefore, it is necessary to metallize the P-type semiconductor and the N-type semiconductor ends with metal electrodes to reduce the resistance and allow the current generated after illumination to enter the electronic device through the metal wire. Among them, the metallization process means that the metal paste is coated or printed at the corresponding position according to requirements, and then the silicon material and the metal are sintered together at high temperature. Usually, silver paste is selected as the material for metallizing with the silicon material. Currently, most manufacturers use screen printing as the method of coating silver paste on the silicon material. Screen printing has the advantages of fast production speed and low cost compared with other methods of forming grid lines by coating silver paste on photovoltaic silicon wafers. Therefore, the screen printing characteristics of silver paste have always been the main focus of improving silver paste products. With the continuous iteration and upgrade of technology, the photoelectric conversion efficiency of solar cells is an important indicator to measure the technology of crystalline silicon solar cells, and the aspect ratio of the grid line height and width after printing directly affects the cell efficiency. In recent years, in addition to the requirement for the aspect ratio of the electrode cross-section obtained from silver paste, there are also higher requirements for printing durability. After the silver paste is printed on the screen plate for a long time and multiple times, the grid lines must remain unbroken, and the line shape and the aspect ratio of the cross-section will not change. Traditional thixotropic agents are limited by their own characteristics and complex dispersion processes, and are prone to the phenomenon of plate plugging and screen blocking, which will greatly affect the photoelectric conversion efficiency of solar cells. At the same time, the problem of downtime for treatment will also cause a reduction in production efficiency. With the progress of the process, the printing performance of the paste has become increasingly important. In addition to no breakage of the grid lines, the grid line width, aspect ratio, and long-term printability must all be taken into account.

[0003] For the existing conductive pastes of solar cells on the market, in order to increase ink permeability, the concentration of resin (thickener) is usually reduced, which easily leads to phase separation of the paste; or during long-term printing, the solvent volatilizes and the paste dries out, which easily causes the phenomenon of broken grid lines. Summary of the Invention

[0004] In order to solve at least one of the above technical problems and develop an organic carrier with low volatility, good dispersibility and stable combination with conductive silver powder, this application provides an organic carrier for a conductive paste of a solar cell, a preparation method, and an application thereof.

[0005] On the one hand, the present application provides an organic carrier for a conductive paste of a solar cell. The organic carrier comprises the following raw materials in parts by weight: 1-30 parts of an elastomer, 6-20 parts of a thickener, 52-90 parts of an organic solvent, and 3-10 parts of an auxiliary agent; the elastomer is a PaMS resin; the auxiliary agent comprises a dispersant and a first surfactant with a weight ratio of 1-3:1-2.

[0006] By adopting the above technical solution, in the organic carrier formulation of the solar cell paste, PaMS (polyalpha-methylstyrene) is used as the elastomer resin and compounded with the thickener. Since PaMS has high solubility in most organic solvents, its carrier and the paste have good stability; at the same time, adding PaMS as the elastomer in the organic solvent can greatly improve the initial viscosity and bonding strength of the organic carrier, and can also greatly reduce the overall volatility of the organic carrier; during long-term screen printing operations, the phenomenon of broken grids is not likely to occur, which can solve the problem of production line stoppage due to poor printing. Polyalpha-methylstyrene can absorb ultraviolet light with a wavelength of 270-330 nm, so it can improve the weather resistance of the prepared electrode to a certain extent.

[0007] Preferably, the organic carrier comprises the following raw materials in parts by weight: 22-30 parts of an elastomer, 6-17 parts of a thickener, 52-69 parts of an organic solvent, and 3-10 parts of an auxiliary agent.

[0008] Preferably, the organic carrier comprises the following raw materials in parts by weight: 26 parts of an elastomer, 14 parts of a thickener, 65 parts of an organic solvent, and 5 parts of a first auxiliary agent.

[0009] Optionally, the glass transition temperature of the elastomer is 160°C - 200°C.

[0010] Optionally, the molecular weight of the elastomer is 800-1000.

[0011] Optionally, the Mooney viscosity (ML 1+4 ) of the elastomer at 100°C is 20-56.

[0012] By adopting the above technical solution, the selection of the Tg value, molecular weight and viscosity of the elastomer enables it to have better compatibility and fluid state when compounded with the thickener, so that the prepared organic carrier has good fluidity, the conductive paste has better dispersibility, and the aggregation phenomenon is avoided.

[0013] Optionally, the thickener is selected from at least one of polybutyl methacrylate, ethyl cellulose, cellulose acetate butyrate, carboxymethyl cellulose, hydroxyethyl cellulose, polyvinyl butyral, rosin resin, polyvinylpyrrolidone.

[0014] By adopting the above technical solution, the thickener and the elastomer are compounded and used to increase the viscosity of the organic carrier and the silver paste prepared therefrom, so that it does not flow, which helps to improve the printing performance of the paste prepared subsequently and the aspect ratio of the printed line deletion.

[0015] Preferably, the thickener is a mixture of cellulose acetate butyrate and polyvinyl butyral with a weight ratio of 1:2 - 5.

[0016] By adopting the above technical solution, it helps to further improve the printing performance of the solar cell conductive paste prepared with this organic carrier.

[0017] Optionally, the organic solvent is selected from at least one of ethylene glycol monobutyl ether, diethylene glycol monobutyl ether, dipropylene glycol monomethyl ether, tripropylene glycol monomethyl ether, ethylene glycol phenyl ether, propylene glycol phenyl ether, ethylene glycol monobutyl ether acetate, diethylene glycol monobutyl ether acetate, dipropylene glycol monomethyl ether acetate, ethylene glycol phenyl ether acetate, propylene glycol phenyl ether acetate, alcohol ester 12, alcohol ester 16, terpineol, terpinol, and dimethyl adipate.

[0018] Preferably, the organic solvent is a mixture of diethylene glycol monobutyl ether and diethylene glycol monobutyl ether acetate with a weight ratio of 2 - 3:1.

[0019] By adopting the above technical solution, using this mixed solvent can better dissolve the elastic resin, thickener, and additives in the organic carrier.

[0020] Optionally, the dispersant is selected from at least one of polyethylene wax, polyethylene glycol, ethylene bisstearamide, monoglyceride stearate, and microcrystalline wax.

[0021] Optionally, the first surfactant includes but is not limited to commercially available surfactants, and can be saturated and unsaturated fatty acids (such as oleic acid), saturated and unsaturated fatty acid amides, coupling agents, and polyoxyethylene type surfactants (such as TritonX - 100, Tween - 20).

[0022] In the second aspect, the present application provides a method for preparing the organic carrier for the above solar cell conductive paste, including the following steps:

[0023] Add the organic solvent, elastomer, thickener, and additives into a container, heat up to 160 - 200 °C, heat for 15 - 30 min, stir while heating, and obtain the organic carrier for the solar cell conductive paste after cooling.

[0024] In the third aspect, the present application provides the application of the above organic carrier in the solar cell conductive paste.

[0025] Optionally, the conductive paste for solar cells comprises raw materials in the following weight percentages: organic carrier 4.5-17 wt%, silver powder 60-92 wt%, glass powder 1-12 wt%, aluminum powder 0-7 wt%, and second surfactant 1-5 wt%.

[0026] In this application, the shape of the silver powder used can be, for example, spherical, flaky or irregular, and the particle size range of the silver powder is 0.1-10 μm; the shape of the aluminum powder used can be, for example, spherical, flaky or irregular, and the particle size range of the aluminum powder is 0.1-10 μm; the particle size range of the glass powder used is 0.1-10 μm.

[0027] Preferably, the conductive paste for solar cells comprises raw materials in the following weight percentages: organic carrier 12.5-15.5 wt%, silver powder 70-92 wt%, glass powder 5.2-7.5 wt%, aluminum powder 0-5 wt%, and second surfactant 1-2 wt%.

[0028] Optionally, the second surfactant includes one or more of silicone oil, silicone oil derivatives, fatty alcohol polyoxyethylene ether, castor oil polyoxyethylene ether, sodium dodecylbenzenesulfonate, saturated and unsaturated fatty acid amides, and other polyoxyethylene type surfactants.

[0029] The preparation method of the conductive paste for solar cells comprises the following steps:

[0030] (1) Put the silver powder, aluminum powder, glass powder, organic carrier and second surfactant into a pre-dispersion container for pre-dispersion to obtain the pre-dispersed paste;

[0031] (2) Grind and disperse the pre-dispersed paste obtained in step (1), and stir to obtain the conductive paste for solar cells.

[0032] In summary, the present invention includes at least one of the following beneficial technical effects:

[0033] 1. In the conductive paste for solar cells in this application, the organic carrier uses PaMS resin as an elastomer, which has high solubility in most organic solvents. Therefore, the prepared organic carrier has good stability in the conductive paste; at the same time, after adding PaMS resin to the organic solvent, the evaporation rate of the organic solvent drops significantly, effectively solving the problem of the printing durability of the paste, maintaining a stable photoelectric conversion efficiency of the solar cell, and not requiring cleaning and wiping due to screen clogging during the printing process, causing the trouble of shutdown.

[0034] 2. Adding PaMS resin as an elastomer into an organic solvent can significantly improve the initial tack and adhesion strength of the organic carrier as a whole. During the printing process of the conductive paste, it can prevent the continuous line expansion due to too low viscosity during the fine grid printing, enabling the prepared grid line to have a higher aspect ratio and improving the photoelectric conversion efficiency of the solar cell. Detailed implementation mode

[0035] The following further elaborates on this application in combination with embodiments.

[0036] This application designs an organic carrier for a solar cell conductive paste, which is characterized in that the organic carrier comprises the following raw materials in parts by weight: 1-30 parts of an elastomer, 6-20 parts of a thickener, 52-90 parts of an organic solvent, and 3-10 parts of an auxiliary agent; the elastomer is PaMS resin;

[0037] The auxiliary agent comprises a dispersant and a second surfactant with a weight ratio of 1-3:1-2.

[0038] The organic carrier for the solar cell conductive paste of this application is prepared by the following method, including the following steps:

[0039] Add the organic solvent, elastomer, thickener, and auxiliary agent into a container, heat up to 160-200 °C, with a heating time of 15-30 min, stir while heating, and obtain the organic carrier for the solar cell conductive paste after cooling.

[0040] The organic carrier for the solar cell conductive paste of this application can be applied in the solar cell conductive paste, and the solar cell conductive paste comprises the following raw materials in weight percentages:

[0041] 4.5-17 wt% of the above-mentioned organic carrier for the solar cell conductive paste, 60-92 wt% of silver powder, 1-12 wt% of glass powder, 0-7 wt% of aluminum powder, and 1-5 wt% of the second surfactant.

[0042] The technical problem to be solved by this application is that for the existing solar cell conductive pastes on the market, in order to increase ink permeability, the concentration of resin (thickener) is usually reduced, which easily leads to phase separation of the paste; or during long-term printing, the solvent volatilization causes the paste to dry out, easily triggering the phenomenon of broken grids. By using PaMS resin as an elastomer in the organic carrier for the solar cell conductive paste of this application and taking advantage of its property of high solubility in most organic solvents, the prepared organic carrier has good stability in the conductive paste. At the same time, after adding PaMS resin to the organic solvent, the volatilization rate of the organic solvent drops significantly, effectively solving the problem of the printing durability of the paste and maintaining a stable photoelectric conversion efficiency of the solar cell chip.

[0043] In this application, the raw materials used in the examples are sourced as follows:

[0044] PaMS resin (poly alpha-methylstyrene resin), CAS No.: 25014-31;

[0045] Cellulose acetate butyrate, CAS No.: 9004-36-8;

[0046] Polyvinyl butyral, CAS No.: 63148-65-2;

[0047] Diethylene glycol butyl ether, CAS No.: 112-34-5;

[0048] Diethylene glycol butyl ether acetate, CAS No.: 124-17-4;

[0049] Polyethylene glycol, CAS No.: 25322-68-3;

[0050] Tween-20, CAS No.: 9005-64-5;

[0051] Silver powder, CAS No.: 7440-22-4;

[0052] Aluminum powder, CAS No.: 7439-89-6.

[0053] Examples 1-7 are organic carriers for conductive pastes of solar cells prepared with different raw material ratios. The specific raw material ratios are shown in Table 1.

[0054] Table 1

[0055] Elastomer (kg) Thickening agent (kg) Dispersant (kg) First surfactant (kg) Organic solvent (kg) Example 1 1 11 3 1 84 Example 2 12 11 3 1 73 Example 3 24 11 3 1 61 Example 4 30 11 3 1 55 Example 5 1 6 2 1 90 Example 6 24 20 3 1 52 Example 7 24 11 6 4 55

[0056] Among them, the elastomer used in Examples 1-7 is PaMS resin; the glass transition temperature of PaMS resin is 175 °C, the average molecular weight of PaMS resin is 850, and the Mooney viscosity (ML 1+4 ) of the elastomer at 100 °C is 32.

[0057] Among them, the thickener used in Examples 1-7 is a mixture of cellulose acetate butyrate and polyvinyl butyral with a weight ratio of 1:3.

[0058] Among them, the organic solvent used in Examples 1-7 is a mixture of diethylene glycol butyl ether and diethylene glycol butyl ether acetate with a weight ratio of 2.5:1.

[0059] Among them, the dispersant used in Examples 1-7 is polyethylene glycol, and the first surfactant used in Examples 1-7 is Tween-20.

[0060] The preparation process of Examples 1-7 is as follows:

[0061] Add the above-mentioned organic solvent, elastomer, thickener and auxiliary agent into a container, heat up to 180 °C, with a heating time of 25 min, stir while heating, and cool to room temperature to obtain an organic carrier for a conductive paste of a solar cell.

[0062] Example 8 is based on Example 3, the difference being that the glass transition temperature of the elastomer, namely PaMS resin, used in Example 8 becomes 160 °C.

[0063] Example 9 is based on Example 3, the difference being that the glass transition temperature of the elastomer, namely PaMS resin, used in Example 9 becomes 200 °C.

[0064] Example 10 is based on Example 3, the difference being that the average molecular weight of the elastomer, namely PaMS resin, used in Example 10 becomes 1000.

[0065] Example 11 is based on Example 3, the difference being that the average molecular weight of the elastomer, namely PaMS resin, used in Example 11 becomes 1200.

[0066] Example 12 is based on Example 3, the difference being that the thickener used in Example 12 is cellulose acetate butyrate.

[0067] Example 13 is based on Example 3, the difference being that the thickener used in Example 13 is polyvinyl butyral.

[0068] Example 14 is based on Example 3, the difference being that the thickener used in Example 14 is rosin resin.

[0069] Example 15 is based on Example 3, the difference being that the thickener used in Example 15 is a mixture of cellulose acetate butyrate and polyvinyl butyral with a weight ratio of 1:1.

[0070] Example 16 is based on Example 3, the difference being that the thickener used in Example 16 is a mixture of ethyl cellulose and polyvinyl butyral with a weight ratio of 1:3.

[0071] Example 17 is based on Example 3, the difference being that the organic solvent used in Example 17 is diethylene glycol butyl ether.

[0072] Example 18 is based on Example 3, the difference being that the organic solvent used in Example 18 is a mixture of diethylene glycol butyl ether and ethylene glycol monobutyl ether acetate with a weight ratio of 1:1.

[0073] Comparative Example 1 is based on Example 3, the difference being that the elastomer used in Comparative Example 1 is replaced by polyamide wax THIXOTROL®MAX.

[0074] Comparative Example 2 was based on Example 3, with the difference that the elastomer used in Comparative Example 2 was replaced with a mixture of polyamide wax THIXOTROL® MAX and PaMS with a weight ratio of 1:1.

[0075] Comparative Example 3 was based on Example 3, with the difference that the amount of PaMS resin in Comparative Example 3 became 40 kg, and at the same time the amount of organic solvent became 45 kg. That is, Comparative Example 3 included 40 kg of PaMS resin, 11 kg of thickener, 3 kg of dispersant, 1 kg of first surfactant, and 45 kg of organic solvent.

[0076] Application Examples 1-18 were solar cell conductive pastes prepared from the organic carriers obtained in Examples 1-18. Among them, the solar cell conductive paste included the following raw materials in weight percentages: 12.5 wt% of organic carrier, 77.5 wt% of silver powder, 7 wt% of glass powder, 2 wt% of aluminum powder, and 1 wt% of second surfactant; among them, the second surfactant was selected as fatty alcohol polyoxyethylene ether; the average particle sizes of silver powder, glass powder, and aluminum powder were all 10 um.

[0077] The preparation process of Application Examples 1-18 was as follows:

[0078] The organic carrier, silver powder, aluminum powder, glass powder, and second surfactant were added to a pre-dispersion container, and then the pre-dispersion container was placed in a planetary dispersion device for pre-dispersion. The dispersed paste was placed in a three-roll mill and rolled 6 times for grinding and dispersion. The ground and dispersed paste was then stirred as a whole once with a stirrer to obtain a solar cell conductive paste.

[0079] Comparative Application Examples 1-3 were solar cell conductive pastes prepared from the organic carriers obtained in Comparative Examples 1-3 of the examples, and other components were the same as those in Application Example 1.

[0080] Performance testing:

[0081] 1. The solar cell conductive pastes prepared in Application Examples 1-18 and Comparative Application Examples 1-3 were screen-printed and sintered on 10 N-type TOPCon silicon wafers each with a screen opening of 14 um and a film thickness of 2.5 um to obtain solar cell wafers with grid lines printed. The line height and line width of the grid lines were measured using a 3D optical microscope, and the number of broken grids on each wafer was observed. The photoelectric conversion efficiency of the solar cell wafers prepared from each conductive silver paste was tested using a device with the model number HSC1 / XSCM-9 produced by Shanghai Jiao Tong University Heshuang Technology Co., Ltd. under standard test conditions (STC). The measurement results are shown in Table 2.

[0082] 2. Storage stability test: The conductive pastes for solar cells prepared in Application Examples 1-18 and Comparative Application Examples 1-3 were hermetically stored at 25°C. After three months, the change in the viscosity of the lower layer of the conductive paste was detected, and whether the silver powder settled was observed. The measurement results are shown in Table 3.

[0083] 3. Visually observe the appearance of the conductive pastes for solar cells prepared in Application Examples 1-18 and Comparative Application Examples 1-3 after screen printing, and observe whether the surface is smooth, whether there are bubbles, and the screen printing uniformity. The measurement results are shown in Table 3.

[0084] Table 2

[0085] Average line width (um) Average line height (um) Aspect ratio (%) Average number of grid segments per piece Average number of broken grids at fixed positions Photoelectric conversion efficiency (%) Application Example 1 28.11 11.86 42.19 4.6 4.2 23.78 Application Example 2 26.94 12.25 45.47 4.2 4 24.55 Application Example 3 24.18 12.43 51.4 2.4 1.6 26.32 Application Example 4 25.24 11.93 47.26 3.9 3.3 24.83 Application Example 5 28.85 11.85 41.08 4.9 4.4 23.42 Application Example 6 24.5 12.22 49.8 2.8 1.9 26.09 Application Example 7 23.25 11.59 48.86 3.5 2.6 25.59 Application Example 8 25.07 11.99 47.82 4.2 3.5 25.33 Application Example 9 24.18 11.65 48.19 3.7 3.1 25.51 Application Example 10 24.26 11.73 48.35 3.6 3 25.59 Application Example 11 26.17 12.11 46.28 4 3.3 24.83 Application Example 12 24.85 11.28 45.39 4.2 3.5 24.38 Application Example 13 24.42 11.62 47.58 4 3.5 24.96 Application Example 14 24.21 11.76 48.58 3.6 3 25.64 Application Example 15 24.06 11.57 48.08 3.8 3.3 25.42 Application Example 16 23.47 11.18 47.64 4.1 3.6 25.13 Application Example 17 23.57 11.35 48.15 3.7 3.2 25.47 Application Example 18 24.48 12.04 49.18 3.2 3.6 25.89 Comparative Application Example 1 30.08 10.93 36.34 17.7 9.4 21.21 Comparative Application Example 2 28.8 11.02 38.26 13.4 7.6 21.45 Comparative Application Example 3 27.01 10.76 39.83 10.5 6.1 22.37

[0086] Table 3

[0087] Appearance of the paste Storage stability Application Example 1 The surface is smooth with a small amount of bubbles and is uniform after printing There is no sedimentation phenomenon after three months Application Example 2 The surface is smooth without bubbles and is uniform after printing There is no sedimentation phenomenon after three months Application Example 3 The surface is smooth without bubbles and is uniform after printing There is no sedimentation phenomenon after three months Application Example 4 The surface is smooth without bubbles and is uniform after printing There is no sedimentation phenomenon after three months Application Example 5 The surface is smooth with a small amount of bubbles and is uniform after printing There is no sedimentation phenomenon after three months Application Example 6 The surface is smooth without bubbles and is uniform after printing There is no sedimentation phenomenon after three months Application Example 7 The surface is smooth without bubbles and is uniform after printing There is no sedimentation phenomenon after three months Application Example 8 The surface is smooth with a small amount of bubbles and is uniform after printing There is no sedimentation phenomenon after three months Application Example 9 The surface is smooth without bubbles and is uniform after printing There is no sedimentation phenomenon after three months Application Example 10 The surface is smooth without bubbles and is uniform after printing There is no sedimentation phenomenon after three months Application Example 11 The surface is smooth without bubbles and is uniform after printing There is no sedimentation phenomenon after three months Application Example 12 The surface is smooth without bubbles and is uniform after printing There is no sedimentation phenomenon after three months Application Example 13 The surface is smooth without bubbles and is uniform after printing There is no sedimentation phenomenon after three months Application Example 14 The surface is smooth without bubbles and is uniform after printing There is no sedimentation phenomenon after three months Application Example 15 The surface is smooth without bubbles and is uniform after printing There is no sedimentation phenomenon after three months Application Example 16 The surface is smooth without bubbles and is uniform after printing There is no sedimentation phenomenon after three months Application Example 17 The surface is smooth without bubbles and is uniform after printing There is no sedimentation phenomenon after three months Application Example 18 The surface is smooth without bubbles and is uniform after printing There is no sedimentation phenomenon after three months Comparative Application Example 1 The surface is not smooth with bubbles The paste caked at the lower layer after three months Comparative Application Example 2 The surface is not smooth with bubbles The paste caked at the lower layer after three months Comparative Application Example 3 The surface is smooth without bubbles and is uniform after printing There is no sedimentation phenomenon after three months

[0088] By analyzing the data in Table 2 and Table 3, Application Examples 1-7 were compared with Comparative Application Examples 1-2; after using PaMS resin as the elastomer of the organic carrier in this application, the printing performance of the conductive silver paste can be significantly improved. The number of broken grids in Application Examples 1-7 is significantly less than that in Comparative Application Example 1-2, and the average line width in Example 1-7 is also narrower, so that the photoelectric conversion efficiency of the solar cell chips in Example 1-7 is significantly higher; the binding property between the organic carrier and the powder in the conductive paste in Application Example 1-7 is better, the conductive paste is not easy to produce phase separation, has good storage stability, the surface smoothness and uniformity after screen printing are better, and there will be no bubbles.

[0089] The above are all preferred embodiments of this application, and the protection scope of this application is not limited accordingly. Therefore, all equivalent changes made according to the structure, shape, and principle of this application should be covered within the protection scope of this application.

Claims

1. An organic carrier for a conductive paste of a solar cell, characterized in that, The organic carrier comprises raw materials in the following parts by weight: 1-30 parts of an elastomer, 6-20 parts of a thickener, 52-90 parts of an organic solvent, and 3-10 parts of an auxiliary agent; The elastomer is a PaMS resin; The auxiliary agent comprises a dispersant and a first surfactant with a weight ratio of 1-3:1-2; The glass transition temperature of the elastomer is 160-175 °C; The molecular weight of the elastomer is 850-1000; The thickener is a mixture of cellulose acetate butyrate and polyvinyl butyral with a weight ratio of 1:3; the organic solvent is a mixture of diethylene glycol monobutyl ether and diethylene glycol monobutyl ether acetate with a weight ratio of 2.5:1; The Mooney viscosity (ML 1+4 ) of the elastomer at 100 °C is 20 - 56.

2. The organic carrier according to claim 1, wherein The dispersant is selected from at least one of polyethylene wax, polyethylene glycol, ethylene bisstearamide, monoglyceride stearate, and microcrystalline wax.

3. A method for preparing the organic carrier according to any one of claims 1-2, characterized in that, It includes the following steps: Adding the organic solvent, elastomer, thickener, and auxiliary agent into a container, heating and raising the temperature to 160-200 °C, with a heating time of 15-30 min, stirring while heating, and obtaining the organic carrier for the conductive paste of the solar cell after cooling.

4. Application of the organic carrier according to any one of claims 1-2 in a conductive paste of a solar cell.

5. The application of the organic carrier according to claim 4 in a conductive paste for a solar cell, characterized in that, The conductive paste of the solar cell comprises raw materials in the following weight percentages: 4.5-17 wt% of the organic carrier according to any one of claims 1-2, 60-92 wt% of silver powder, 1-12 wt% of glass powder, 0-7 wt% of aluminum powder, and 1-5 wt% of a second surfactant.