Conductive nickel paste, preparation method thereof and solar cell piece

Abstract

This application relates to the photovoltaic field, providing a conductive nickel paste, its preparation method, and a solar cell. The conductive nickel paste comprises the following components by weight percentage: nickel powder: 50.0%~74.0%, silver powder: 15%~30%, glass powder: 0.5%~5.0%, organic solvent: 2%~20.0%, resin: 0.3%~2.0%, and additives: 0.1%~5.0%. The nickel powder includes a first nickel powder with a D50 of 0.2μm~1.4μm and a second nickel powder with a D100 of 0.5μm~4μm, and the surface of the nickel powder is coated with organic matter. The technical solution provided by this application has at least the following advantages: 1. The conductive nickel paste can form a uniform and dense conductive layer, significantly reducing resistivity and improving current transmission efficiency, thereby improving the photoelectric conversion efficiency of the solar cell; 2. In terms of compatibility, the conductive nickel paste can reduce interfacial reactions with other photovoltaic materials (such as silicon substrates and passivation layers), extending the service life of the module in humid and hot environments.

Description

Technical Field

[0001] This application relates to the photovoltaic field, and in particular to a conductive nickel paste, its preparation method, and a solar cell. Background Technology

[0002] In the increasingly competitive solar photovoltaic industry, the goal of major companies is to produce superior solar cells at a lower cost. Photovoltaic silver paste is expensive, and using base metal pastes with good conductivity as alternatives is a direction the industry is currently exploring. Summary of the Invention

[0003] This application provides a conductive nickel paste, its preparation method, and a solar cell, which at least helps to solve the problems of high cost and reduced passivation effect of traditional solar silver paste due to reaction with the passivation interface.

[0004] According to some embodiments of this application, one aspect of this application provides a conductive nickel paste for the manufacture of solar cells, comprising the following components by weight percentage: Nickel powder: 50.0%~74.0%, Silver powder: 15%~30%, Glass powder: 0.5%~5.0%, Organic solvents: 2%~20.0%, Resin: 0.3%~2.0%, Additives: 0.1%~5.0%, The nickel powder includes a first nickel powder with a D50 of 0.2μm to 1.4μm and a second nickel powder with a D100 of 0.5μm to 4μm. The surfaces of the first nickel powder and the second nickel powder are modified by a first organic compound. The surface of the silver powder is coated with a second organic compound.

[0005] In some embodiments, the weight ratio of the first nickel powder to the second nickel powder is 1:(3~20).

[0006] In some embodiments, the nickel powder includes spherical nickel powder and flake nickel powder, wherein the surface of the spherical nickel powder is smooth or has spikes.

[0007] In some embodiments, the nickel powder is a mixture of flake nickel powder and spherical nickel powder with spikes on the surface in a weight ratio of (1.5~5):1.

[0008] In some embodiments, the first organic compound and the second organic compound each independently include at least one of oleic acid, silane coupling agent, linoleic acid, stearic acid, lauric acid, and amine compounds.

[0009] In some embodiments, the glass powder comprises a first glass powder with D50 < 1.6 μm and a second glass powder with D100 < 4.0 μm.

[0010] In some embodiments, the first glass powder and the second glass powder have the same composition, both comprising the following components in molar percentage: First component: 40%~55%, Second component: 15%~30%, Third component: 2%~10%, Fourth component: 1%~10%, Modified additives: 1%~10%, The first component is a mixture of PbO and BaO, the second component is a mixture of SiO2 and GeO2, the third component is a mixture of B2O3, Al2O3 and Ga2O3, the fourth component is a mixture of Ag2O and Li2O, and the modifying additive is at least one of MgO, CaO, BaO, ZnO, Bi2O3 and SeO2, or a compound that can be decomposed to obtain at least one of MgO, CaO, BaO, ZnO, Bi2O3 and SeO2 during the preparation of glass powder.

[0011] In some embodiments, the method for preparing the glass powder includes the following steps: The raw materials are mixed according to the stoichiometric ratio, melted at the first temperature, and then water-quenched, dried, and pulverized to obtain glass powder.

[0012] In some embodiments, the first temperature is 900°C to 1300°C.

[0013] In some embodiments, the particle size of the silver powder is 150 nm to 750 nm.

[0014] In some embodiments, the organic resin includes at least one of ethyl cellulose, hydroxyethyl cellulose, acrylic resin, polyurethane, epoxy resin, cellulose acetate butyrate, terpene resin, and SEBS.

[0015] In some embodiments, the organic solvent includes at least one of alcohols, ketones, esters, aliphatic hydrocarbons, aromatic hydrocarbons, and naphtha.

[0016] In some embodiments, the alcohol compounds include at least one or more of n-propanol, n-pentanol, 2-methylbutanol, ethylene glycol butyl ether, diethylene glycol butyl ether, trimethylnonanol, and methyl isobutyl methanol; the ketone compounds include at least one of methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone, and isoflurane diisobutyl ketone; the ester compounds include at least one of methyl acetate, ethyl acetate, and n-butyl acetate dicarboxylate; and the aromatic hydrocarbon compounds include at least one of high-boiling-point aromatic solvents such as toluene, xylenes, n-propyl methoxybenzene, anthracene and its derivatives, and phenanthrene and its derivatives.

[0017] In some embodiments, the additives include at least one or more of wetting and dispersing agents, defoamers, and antisettling agents.

[0018] In some embodiments, the wetting and dispersing agent includes ED-120; the defoamer includes BYK141; and the anti-settling agent includes BYK4510.

[0019] According to some embodiments of this application, another aspect of this application provides a method for preparing conductive nickel paste, which includes the following steps: After mixing organic solvent, resin and additives, glass powder is added and dispersed evenly. Silver powder and nickel powder are then added, stirred and rolled to obtain conductive nickel paste.

[0020] According to some embodiments of this application, another aspect of this application provides a method for manufacturing a solar cell, characterized in that it includes: Provide battery body; Provide a conductive nickel paste as described in any of the above embodiments, and print the conductive nickel paste onto the battery body to form an electrode pattern; and perform a sintering process on the electrode pattern to form grid lines.

[0021] According to some embodiments of this application, another aspect of this application provides a solar cell, wherein the grid lines of the solar cell are formed using conductive nickel paste as described in any of the above embodiments, or obtained by the manufacturing method of the solar cell described in the above embodiments.

[0022] The technical solution provided in this application has at least the following advantages: 1. Conductive nickel paste can form a uniform and dense conductive layer, which significantly reduces resistivity and improves current transmission efficiency, thereby improving the photoelectric conversion efficiency of solar cells. 2. Conductive nickel paste can reduce interfacial reactions with other photovoltaic materials (such as silicon substrates and passivation layers) in terms of compatibility, and extend the service life of the module in humid and hot environments. 3. Compared to the dominant conductive silver paste, conductive nickel paste has lower raw material costs, which can reduce metallization costs by about 15% to 20% in the solar cell manufacturing process. Attached Figure Description

[0023] One or more embodiments are illustrated by way of example with reference to the accompanying drawings. These illustrations do not constitute a limitation on the embodiments. Unless otherwise stated, the drawings in the accompanying drawings do not constitute a limitation on scale. In order to more clearly illustrate the technical solutions in the embodiments of this application or in the conventional art, the drawings used in the embodiments will be briefly introduced below. Obviously, the 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.

[0024] Figure 1 This application demonstrates the effect of the conductive silver paste in reducing the contact resistance and specific contact resistance of solar cells. Detailed Implementation

[0025] As the background technology indicates, traditional conductive silver paste for solar cells is costly and the international silver powder market is volatile. Silver, as an excellent conductor, is prone to interfacial reactions with photovoltaic materials, affecting electron transport in solar cells and potentially leading to passivation failure at the solar cell interface.

[0026] According to some embodiments of this application, one aspect of this application provides a conductive nickel paste for the manufacture of solar cells, comprising the following components by weight percentage: Nickel powder: 50.0%~74.0%, Silver powder: 15%~30%, Glass powder: 0.5%~5.0%, Organic solvents: 2%~20.0%, Resin: 0.3%~2.0%, Additives: 0.1%~5.0%, In some embodiments, the nickel powder includes a first nickel powder with a D50 of 0.2 μm to 1.4 μm and a second nickel powder with a D100 of 0.5 μm to 4 μm, and the surface of the nickel powder is coated with organic matter.

[0027] In some embodiments, the weight ratio of the first nickel powder to the second nickel powder is 1:(3~20).

[0028] In some embodiments, the nickel powder may be in the shape of at least one of flakes and spheres with spikes on the surface.

[0029] In some embodiments, the nickel powder is a mixture of flake nickel powder and spherical nickel powder with spikes on the surface in a weight ratio of (1.5~5):1.

[0030] In some embodiments, the organic compound includes at least one of oleic acid, silane coupling agent, linoleic acid, stearic acid, and lauric acid.

[0031] In some embodiments, the glass powder comprises a first glass powder with D50 < 1.6 μm and a second glass powder with D100 < 4.0 μm.

[0032] In some embodiments, the first glass powder and the second glass powder have the same composition, both comprising the following components in molar percentage: First component: 40%~55%, Second component: 15%~30%, Third component: 2%~10%, Fourth component: 1%~10%, Modified additives: 1%~10%, The first component is a mixture of PbO and BaO, the second component is a mixture of SiO2 and GeO2, the third component is a mixture of B2O3, Al2O3 and Ga2O3, the fourth component is a mixture of Ag2O and Li2O, and the modifying additive is at least one of MgO, CaO, BaO, ZnO, Bi2O3 and SeO2, or a compound that can be decomposed to obtain at least one of MgO, CaO, BaO, ZnO, Bi2O3 and SeO2 during the preparation of glass powder.

[0033] In some embodiments, the method for preparing the glass powder includes the following steps: The raw materials are mixed according to the stoichiometric ratio, melted at the first temperature, and then water-quenched, dried, and pulverized to obtain glass powder.

[0034] In some embodiments, the first temperature is 900°C to 1300°C.

[0035] In some embodiments, the particle size of the silver powder is 150 nm to 750 nm.

[0036] In some embodiments, the organic resin includes at least one of ethyl cellulose, hydroxyethyl cellulose, acrylic resin, polyurethane, epoxy resin, cellulose acetate butyrate, terpene resin, and SEBS.

[0037] In some embodiments, the organic solvent includes at least one of alcohols, ketones, esters, aliphatic hydrocarbons, aromatic hydrocarbons, and naphtha.

[0038] In some embodiments, the alcohol compounds include at least one or more of n-propanol, n-pentanol, 2-methylbutanol, ethylene glycol butyl ether, diethylene glycol butyl ether, trimethylnonanol, and methyl isobutyl methanol; the ketone compounds include at least one of methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone, and isoflurane diisobutyl ketone; the ester compounds include at least one of methyl acetate, ethyl acetate, and n-butyl acetate dicarboxylate; and the aromatic hydrocarbon compounds include at least one of xylene and high-boiling-point aromatic solvents.

[0039] In some embodiments, the additives include at least one or more of wetting and dispersing agents, defoamers, and antisettling agents.

[0040] In some embodiments, the wetting and dispersing agent includes ED-120; the defoamer includes BYK141; and the anti-settling agent includes BYK4510.

[0041] According to some embodiments of this application, another aspect of this application provides a method for preparing conductive nickel paste, which includes the following steps: After mixing organic solvent, resin and additives, glass powder is added and dispersed evenly. Silver powder and nickel powder are then added, stirred and rolled to obtain conductive nickel paste.

[0042] According to some embodiments of this application, another aspect of this application provides a method for manufacturing a solar cell, characterized in that it includes: Provide battery body; Provide a conductive nickel paste as described in any of the above embodiments, and print the conductive nickel paste onto the battery body to form an electrode pattern; and perform a sintering process on the electrode pattern to form grid lines.

[0043] According to some embodiments of this application, another aspect of this application provides a solar cell, wherein the grid lines of the solar cell are formed using conductive nickel paste as described in any of the above embodiments, or obtained by the preparation method described in any of the above embodiments.

[0044] In the description of the embodiments of this application, technical terms such as "first" and "second" are used only to distinguish different objects and should not be construed as indicating or implying relative importance or implicitly specifying the number, specific order, or primary and secondary relationship of the indicated technical features. In the description of the embodiments of this application, "multiple" means two or more, unless otherwise explicitly defined.

[0045] In this document, the term "embodiment" means that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of this application. The appearance of this phrase in various places throughout the specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment mutually exclusive with other embodiments. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments.

[0046] In the description of the embodiments in this application, the term "and / or" is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent three cases: A exists, A and B exist simultaneously, and B exists. In addition, the character " / " in this document generally indicates that the related objects before and after it have an "or" relationship.

[0047] In the description of the embodiments of this application, the term "multiple" refers to two or more (including two), similarly, "multiple sets" refers to two or more (including two sets), and "multiple pieces" refers to two or more (including two pieces).

[0048] In the description of the embodiments of this application, the technical terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing the embodiments of this application and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the embodiments of this application.

[0049] In the description of the embodiments of this application, unless otherwise expressly specified and limited, the technical terms such as "installation," "connection," "joining," and "fixing" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. For those skilled in the art, the specific meaning of the above terms in the embodiments of this application can be understood according to the specific circumstances.

[0050] In the accompanying drawings corresponding to the embodiments of this application, the thickness and area of ​​the layers are enlarged for better understanding and ease of description. When describing a component (such as a layer, film, region, or substrate) on or on the surface of another component, the component may be "directly" located on the surface of the other component, or there may be a third component between the two components. Conversely, when describing a component on the surface of another component, or when another component is formed or disposed on the surface of a component, it indicates that there is no third component between the two components. Furthermore, when describing a component as being "generally" formed on another component, it means that the component is not formed on the entire surface (or front surface) of the other component, nor is it formed on a portion of the edge of the entire surface.

[0051] In the description of the embodiments of this application, when a component "includes" another component, other components are not excluded unless otherwise stated, and other components may be further included. Furthermore, when a component such as a layer, film, region, or plate is referred to as being "on / located" on another component, it can be "directly on" the other component (i.e., located on the surface of the other component with no other components between them), or another component may be present therein. Moreover, when a component such as a layer, film, region, or plate is "directly located" on another component, or when a component such as a layer, film, region, or plate is located on the surface of another component, it indicates that no other components are located therein.

[0052] The terminology used in the description of the various embodiments herein is for the purpose of describing particular embodiments only and is not intended to be limiting. As used in the description of the various embodiments and the appended claims, the term "part" is also intended to include the plural form unless the context clearly indicates otherwise. Components include layers, films, regions, or plates, etc.

[0053] The embodiments of this application will now be described in detail with reference to the accompanying drawings. However, those skilled in the art will understand that many technical details have been provided in the embodiments of this application to facilitate a better understanding of the application. However, the technical solutions claimed in this application can be implemented even without these technical details and various variations and modifications based on the following embodiments.

[0054] The manufacturers and models of the silver and nickel powders used in the embodiments of this application are shown in Table 1.

[0055] Table 1

[0056] Example 1 This embodiment provides a method for preparing conductive nickel paste, including the following steps: The raw materials are prepared according to the proportions in Table 2. The nickel powder includes a first nickel powder with a D50 of 0.45 μm (nickel powder 1 in Table 1) and a second nickel powder with a D100 of 1.0 μm (nickel powder 3 in Table 1). The proportions of the first and second nickel powders are shown in Table 3. The glass powder is prepared according to the proportions shown in Table 4: the first component (a mixture of PbO and BaO), the second component (a mixture of SiO2 and GeO2), the third component (a mixture of B2O3, Al2O3 and Ga2O3), the fourth component (a mixture of Ag2O and Li2O) and the modified additive (BaO) are mixed evenly, melted at 900℃, and then water-quenched, dried and pulverized to obtain glass powder. The organic solvent is n-propanol, the resin is ethyl cellulose, and the additive is ED-120.

[0057] After mixing the organic solvent, resin and additives, glass powder is added and dispersed evenly. Then, silver powder (silver powder 1 in Table 1) and nickel powder are added and stirred. The mixture is then rolled 6 times on a three-roll mill to further disperse and homogenize it. When the scraper fineness is less than 5μm, it is filtered with a 400-mesh filter cloth to obtain conductive nickel paste.

[0058] Example 2 This embodiment provides a method for preparing conductive nickel paste, including the following steps: The raw materials are prepared according to the proportions in Table 2. The nickel powder includes a first nickel powder with a D50 of 0.45 μm (nickel powder 1 in Table 1) and a second nickel powder with a D100 of 1.0 μm (nickel powder 3 in Table 1). The proportions of the first and second nickel powders are shown in Table 3. The glass powder is prepared according to the proportions shown in Table 4: the first component (a mixture of PbO and BaO), the second component (a mixture of SiO2 and GeO2), the third component (a mixture of B2O3, Al2O3 and Ga2O3), the fourth component (a mixture of Ag2O and Li2O) and the modified additive (ZnO) are mixed evenly, melted at 1000℃, and then water-quenched, dried and pulverized to obtain glass powder. The organic solvent is n-pentanol, the resin is hydroxyethyl cellulose, and the additive is BYK141.

[0059] After mixing the organic solvent, resin and additives, glass powder is added and dispersed evenly. Then, silver powder (silver powder 2 in Table 1) and nickel powder are added and stirred. The mixture is then rolled 6 times on a three-roll mill to further disperse and homogenize it. When the scraper fineness is less than 5μm, it is filtered with a 400-mesh filter cloth to obtain conductive nickel paste.

[0060] Example 3 This embodiment provides a method for preparing conductive nickel paste, including the following steps: The raw materials are prepared according to the proportions in Table 2. The nickel powder includes a first nickel powder with a D50 of 0.45 μm (nickel powder 1 in Table 1) and a second nickel powder with a D100 of 3.3 μm (nickel powder 4 in Table 1). The proportions of the first and second nickel powders are shown in Table 3. The glass powder is prepared according to the proportions shown in Table 4: the first component (a mixture of PbO and BaO), the second component (a mixture of SiO2 and GeO2), the third component (a mixture of B2O3, Al2O3 and Ga2O3), the fourth component (a mixture of Ag2O and Li2O) and the modified additive (MgO) are mixed evenly, melted at 1100℃, and then water-quenched, dried and pulverized to obtain glass powder. The organic solvent is 2-methylbutanol, the resin is acrylic resin and the additive is BYK4510.

[0061] After mixing the organic solvent, resin and additives, glass powder is added and dispersed evenly. Then, silver powder (silver powder 1 in Table 1) and nickel powder are added and stirred. The mixture is then rolled 6 times on a three-roll mill to further disperse and homogenize it. When the scraper fineness is less than 5μm, it is filtered with a 400-mesh filter cloth to obtain conductive nickel paste.

[0062] Example 4 This embodiment provides a method for preparing conductive nickel paste, including the following steps: The raw materials are prepared according to the proportions in Table 2. The nickel powder includes a first nickel powder with a D50 of 1.2 μm (nickel powder 1 in Table 1) and a second nickel powder with a D100 of 3.3 μm (nickel powder 4 in Table 1). The proportions of the first and second nickel powders are shown in Table 3. The glass powder is prepared according to the proportions shown in Table 4: the first component (a mixture of PbO and BaO), the second component (a mixture of SiO2 and GeO2), the third component (a mixture of B2O3, Al2O3 and Ga2O3), the fourth component (a mixture of Ag2O and Li2O) and the modified additive (SiO2) are mixed evenly, melted at 1200℃, and then water-quenched, dried and pulverized to obtain glass powder. The organic solvent is ethylene glycol butyl ether, the resin is epoxy resin, and the additives are ED-120 and BYK141.

[0063] After mixing the organic solvent, resin and additives, glass powder is added and dispersed evenly. Then, silver powder (silver powder 2 in Table 1) and nickel powder are added and stirred. The mixture is then rolled 6 times on a three-roll mill to further disperse and homogenize it. When the scraper fineness is less than 5μm, it is filtered with a 400-mesh filter cloth to obtain conductive nickel paste.

[0064] Example 5 This embodiment provides a method for preparing conductive nickel paste, including the following steps: The raw materials are prepared according to the proportions in Table 2. The nickel powder includes a first nickel powder with a D50 of 1.2 μm (nickel powder 1 in Table 1) and a second nickel powder with a D100 of 3.3 μm (nickel powder 4 in Table 1). The proportions of the first and second nickel powders are shown in Table 3. The glass powder is prepared according to the proportions shown in Table 4: the first component (a mixture of PbO and BaO), the second component (a mixture of SiO2 and GeO2), the third component (a mixture of B2O3, Al2O3 and Ga2O3), the fourth component (a mixture of Ag2O and Li2O) and the modified additive (SeO2) are mixed evenly, melted at 1300℃, and then water-quenched, dried and pulverized to obtain glass powder. The organic solvent is methyl ethyl ketone, the resin is acrylic resin, and the additives are BYK141 and BYK4510.

[0065] After mixing the organic solvent, resin and additives, glass powder is added and dispersed evenly. Then, silver powder (silver powder 2 in Table 1) and nickel powder are added and stirred. The mixture is then rolled 6 times on a three-roll mill to further disperse and homogenize it. When the scraper fineness is less than 5μm, it is filtered with a 400-mesh filter cloth to obtain conductive nickel paste.

[0066] Table 2

[0067] Table 3

[0068] Table 4

[0069] Comparative Example 1 The only difference between this comparative example and Example 1 is that the second nickel powder was not used, and the missing weight was made up with the first nickel powder.

[0070] Comparative Example 2 The only difference between this comparative example and Example 1 is that the first nickel powder was not used, and the missing weight was made up with the second nickel powder.

[0071] Comparative Example 3 The only difference between this comparative example and Example 1 is that the weight ratio of the first nickel powder and the second nickel powder is 1:1.

[0072] Comparative Example 4 The only difference between this comparative example and Example 1 is that 50% of the second nickel powder was removed, and the missing weight was made up with flake nickel powder (i.e., nickel powder 4 in Table 1).

[0073] Comparative Example 5 The only difference between this comparative example and Example 1 is that spherical nickel powder with spikes on the surface was not used, and the missing weight was made up with flake nickel powder (i.e., nickel powder 4 in Table 1).

[0074] Table 5

[0075] The conductive nickel paste prepared in this application embodiment can effectively reduce the contact resistance of solar cells and increase the fill factor (FF), thereby improving the photoelectric conversion efficiency of solar cells.

[0076] As shown in Table 5, from Examples 1, 2, 3, and 5, it can be seen that when the sum of silver powder and nickel powder is higher than 80%, the photoelectric conversion efficiency of the solar cell remains stable; combined with Example 4, when the sum of silver powder and nickel powder is lower than 75%, it has a negative impact on the photoelectric conversion efficiency of the solar cell.

[0077] Comparing Comparative Examples 1 and 2 with Example 1, it was found that the absence of either the first or second nickel powder negatively impacts the photoelectric conversion efficiency of the solar cell. Voc, FF, and Isc all decrease accordingly.

[0078] Comparing Comparative Example 3 with Example 1, the solar cell efficiency was reduced, indicating that the weight ratio of the first nickel powder and the second nickel powder has an optimal range.

[0079] Comparing Comparative Examples 4 and 5 with Example 1, the solar cell efficiency was reduced, indicating that the optimal range of the ratio of spherical nickel powder and barbed spherical nickel powder is available, and that it needs to be combined with flake nickel powder to achieve the best efficiency.

[0080] The conductive nickel paste prepared in this application embodiment can reduce the contact resistance and specific contact resistivity of solar cells, thereby improving the photoelectric conversion efficiency of solar cells, based on a paste with 100% silver as the conductive phase. As shown in Examples 3 and 5, the fill factor (FF) of the solar cell is improved by applying the method of this invention, thereby improving the efficiency of the solar cell; tests have shown that the improvement in fill factor comes from the reduction in contact resistance and contact resistivity (e.g., ...). Figure 1 (As shown).

[0081] Those skilled in the art will understand that the above embodiments are specific examples of implementing this application, and in practical applications, various changes in form and detail can be made without departing from the spirit and scope of this application. Any person skilled in the art can make various alterations and modifications without departing from the spirit and scope of this application; therefore, the scope of protection of this application should be determined by the scope defined in the claims.

Claims

1. A conductive nickel paste for manufacturing solar cells, characterized in that, Includes the following components by weight percentage: Nickel powder: 50.0%~74.0%, Silver powder: 15%~30%, Glass powder: 0.5%~5.0%, Organic solvents: 2%~20.0%, Resin: 0.3%~2.0%, Additives: 0.1%~5.0%, The nickel powder includes a first nickel powder with a D50 of 0.2μm to 1.4μm and a second nickel powder with a D100 of 0.5μm to 4μm. The surfaces of the first nickel powder and the second nickel powder are modified by a first organic compound. The surface of the silver powder is coated with a second organic compound. The weight ratio of the first nickel powder to the second nickel powder is 1:(3~20); the nickel powder includes spherical nickel powder and flake nickel powder, and the surface of the spherical nickel powder is smooth or has sharp points; Both the first organic compound and the second organic compound independently include at least one of oleic acid, silane coupling agent, linoleic acid, stearic acid, lauric acid, and amine compounds; The glass powder comprises a first glass powder with D50 < 1.6 μm and a second glass powder with D100 < 4.0 μm; the first and second glass powders have the same composition, both comprising the following components in molar percentage: First component: 40%~55%, Second component: 15%~30%, Third component: 2%~10%, Fourth component: 1%~10%, Modified additives: 1%~10%, The first component is a mixture of PbO and BaO, the second component is a mixture of SiO2 and GeO2, the third component is a mixture of B2O3, Al2O3 and Ga2O3, the fourth component is a mixture of Ag2O and Li2O, and the modifying additive is at least one of MgO, CaO, BaO, ZnO, Bi2O3 and SeO2, or a compound that can be decomposed to obtain at least one of MgO, CaO, BaO, ZnO, Bi2O3 and SeO2 during the preparation of glass powder.

2. The conductive nickel paste according to claim 1, characterized in that, The nickel powder is a mixture of flake nickel powder and spherical nickel powder in a weight ratio of (1.5~5):

1.

3. The conductive nickel paste according to claim 1, characterized in that, The method for preparing the glass powder includes the following steps: The raw materials are mixed according to the stoichiometric ratio, melted at the first temperature, and then water-quenched, dried, and pulverized to obtain glass powder.

4. The conductive nickel paste according to claim 3, characterized in that, The first temperature is 900℃~1300℃.

5. The conductive nickel paste according to claim 1, characterized in that, The silver powder has a particle size of 150nm~750nm.

6. A method for preparing conductive nickel paste as described in any one of claims 1 to 5, characterized in that, Includes the following steps: After mixing organic solvent, resin and additives, glass powder is added and dispersed evenly. Silver powder and nickel powder are then added, stirred and rolled to obtain conductive nickel paste.

7. A method for manufacturing a solar cell, characterized in that, include: Provide battery body; Provide a conductive nickel paste as described in any one of claims 1 to 6, and print the conductive nickel paste onto the battery body to form an electrode pattern; and perform a sintering process on the electrode pattern to form grid lines.

8. A solar cell, characterized in that, The grid lines of the solar cell are formed using the conductive nickel paste described in any one of claims 1 to 6, or obtained by the method for manufacturing a solar cell as described in claim 7.

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