CN115836033A

CN115836033A - Glass frit and preparation method thereof, conductive paste, preparation method thereof and solar cell

Info

Publication number: CN115836033A
Application number: CN202280003092.1A
Authority: CN
Inventors: 谭祥虎; 张�杰; 李德林
Original assignee: Soltrium Advanced Materials Technology Ltd Shenzhen
Current assignee: Soltrium Advanced Materials Technology Ltd Shenzhen
Priority date: 2022-09-08
Filing date: 2022-09-08
Publication date: 2023-03-21
Also published as: WO2024050767A1

Abstract

The application relates to the technical field of solar cell materials, in particular to a glass material and a preparation method thereof, conductive paste and a preparation method thereof, and a solar cell. The application provides a glass material in a first aspect, which comprises the following raw material components in percentage by mass: 30 to 50 percent of lead oxide, 15 to 30 percent of boron oxide, 20 to 30 percent of silicon dioxide, 1 to 10 percent of aluminum oxide, 0.5 to 5 percent of zinc oxide, 0 to 7 percent of nickel oxide or/and germanium oxide and 10 to 20 percent of cobalt-containing compound. The application can provide splendid static electric conductive property in the cobalt-containing compound that introduces in the glass powder, collects active material's microcurrent to reduce contact resistance by a wide margin, can improve the adhesive force between the two simultaneously, collocation germanium oxide and nickel oxide make the glass powder together, can reduce contact resistance in coordination in the electrically conductive thick liquids system, improve photoelectric conversion efficiency, can promote battery open circuit voltage.

Description

Glass frit and preparation method thereof, conductive paste, preparation method thereof and solar cell

Technical Field

The application belongs to the technical field of solar cell materials, and particularly relates to a glass material, a preparation method of the glass material, conductive paste, a preparation method of the conductive paste and a solar cell.

Background

In the related art, an antireflection film (mostly a silicon nitride film layer) is arranged on a silicon substrate of the silicon solar cell, a grid line pattern is arranged on the antireflection film, and a front electrode formed by front conductive silver paste is arranged in the grid line pattern. In the manufacturing process of the silicon solar cell, firstly, an antireflection film is plated on a silicon substrate by methods such as vapor deposition and the like, then a photoetching process or laser penetrates through the antireflection film to prepare a grid line pattern, then front conductive silver paste is printed in a grid line in a screen printing mode, the antireflection film is corroded by the front conductive silver paste through sintering, and then the front conductive silver paste can be contacted with the silicon substrate; after sintering, the conductive silver paste forms a grid-line-type front electrode on the surface of the silicon substrate.

Specifically, the conductive silver paste used for manufacturing the front electrode generally includes three parts, i.e., a conductive phase (silver powder) which plays a role of conducting electricity as the name implies, an organic vehicle which is a solution of a polymer (e.g., resin, cellulose, etc.) dissolved in an organic solvent and is a vehicle for the conductive phase and the binder phase, and plays a role of dispersing the conductive phase and the binder phase, and mixing the conductive phase and the binder phase for screen printing; the bonding phase comprises glass powder, and the glass powder can be melted after being sintered after the conductive silver paste is printed on the antireflection film, and plays a role in corroding the antireflection film and bonding the conductive phase and the substrate; more specifically, after the conductive silver paste is screen-printed on the silicon substrate, the anti-reflection film can be corroded by sintering the conductive silver paste and the silicon substrate to convert the glass powder into a molten state, so that the conductive phase in the conductive silver paste is in contact with the silicon substrate (at this time, the silver powder serving as the conductive phase is dissolved in the molten glass phase in the form of silver ions); and then, the conductive silver paste is shrunk into a solid object integrally, so that the conductive silver paste is in electric contact with the silicon substrate, and a grid-line type front electrode is formed.

Therefore, as an important component of silver paste, the glass frit plays a crucial role, which not only helps to form a silver-silicon ohmic contact, provides solderable properties to a silver electrode, but also affects sintering activity of silver powder, etc. For the silver-aluminum paste of the N-type solar cell, the glass frit is an important factor for determining the contact resistance, the surface etching reaction and the electrical performance of the whole cell, only a passivation layer penetrating through the surface needs to be etched in the etching process, and the doped polysilicon layer is etched less and forms excellent contact, so that the development of a novel high-efficiency glass frit is particularly important.

At present, the problems of high sintering temperature, large surface recombination and low photoelectric conversion efficiency exist in the silver-aluminum paste glass material of the N-type crystalline silicon solar cell, and the existing improved technical scheme focuses on the aspects of increasing ohmic contact, reducing recombination, increasing open voltage, reducing contact resistance and the like.

Disclosure of Invention

Technical problem

The technical problem that this application will solve is: the invention provides a glass material and a preparation method thereof, a conductive paste, a preparation method thereof and a solar cell, and aims to solve the problems of high sintering temperature, large surface recombination and low photoelectric conversion efficiency of the silver-aluminum paste glass material of the existing N-type crystalline silicon solar cell.

Further, the application also provides the conductive paste, a preparation method and a solar cell.

Technical solution

In order to achieve the above purpose, the technical solution adopted by the present application is as follows:

the glass frit for the N-type crystalline silicon solar cell comprises the following raw material components in percentage by mass:

correspondingly, the preparation method of the glass frit comprises the following steps:

weighing the components according to the mass percent of the raw materials contained in the glass frit in the text;

mixing and melting the raw materials to obtain the glass frit.

And the conductive paste comprises conductive metal particles and also comprises the glass frit in the paper or the glass frit prepared by the preparation method of the glass frit in the paper.

Correspondingly, the preparation method of the conductive paste comprises the following steps: and mixing the conductive metal particles and the glass frit to obtain the conductive paste.

And the N-type TOPCon crystal silicon solar cell is formed by curing the conductive paste.

Advantageous effects

Compared with the prior art, the glass powder provided by the embodiment of the application can provide some trace elements for the glass powder by adjusting the compound ratio of the components such as lead oxide, boron oxide, silicon dioxide, aluminum oxide, zinc oxide, nickel oxide or/and germanium oxide, germanium oxide and cobalt-containing compound, and special trace elements are added into the glass powder to improve the electrical property of the glass powder. In a second aspect, the cobalt-containing compound introduced into the glass powder in the embodiment of the present application can provide excellent static conductivity, can collect microcurrent of active substances, is applied to an N-type crystalline silicon solar cell, can greatly reduce contact resistance, and can improve the adhesion capability between the glass powder and a doped crystalline silicon layer, and meanwhile, the glass powder is prepared by matching germanium oxide or/and nickel oxide, so that the contact resistance can be synergistically reduced in a system, the photoelectric conversion efficiency is improved, and the glass powder has excellent contact performance with the crystalline silicon layer, so that the open-circuit voltage of the N-type crystalline silicon solar cell can be improved, and further, the overall performance of the N-type crystalline silicon solar cell is improved.

The preparation method of the glass frit mainly comprises two steps. Step one, weighing the components according to the mass percent of the raw materials contained in the glass frit, and reducing the sintering temperature of the glass frit. The glass raw materials are mixed to obtain a highly dispersed glass raw material mixture, so that the subsequent forming treatment of the glass raw materials is facilitated. And secondly, mixing and melting the raw materials to form liquid glass frit, wherein the glass frit prepared by the preparation method of the glass frit has lower contact resistance and higher photoelectric conversion efficiency in a silver paste system and forms excellent contact with a crystalline silicon layer.

The conductive paste provided by the application can reduce the contact resistance of the conductive paste and improve the photoelectric conversion efficiency of the conductive paste through the synergistic effect of the conductive metal particles and the glass frit in the conductive paste. The conductive paste formed by compounding the glass frit and the conductive agent provided by the embodiment of the application has the conductive performance given by the conductive agent, so that the conductive layer is formed.

The conductive paste formed by compounding the glass material and the conductive metal particles has the advantages that the conductive agent endows the conductive paste with conductive performance, and the conductive paste is convenient to coat to form a conductive layer. The glass frit has low metal induced recombination, so that the open circuit voltage of the conductive paste is improved, and the conductive paste has excellent contact resistivity at a low sintering temperature. In addition, the cobalt-containing glass frit of the embodiment of the application also supports an ultrathin polysilicon layer, has higher adhesion strength, and can reduce the contact resistance.

The cobalt-containing glass material can be used for preparing the front silver-aluminum paste of the N-type crystalline silicon solar cell, so that the open-circuit voltage of the N-type TOPCon crystalline silicon solar cell can be improved. The solar cell comprises an N-type TOPCon crystalline silicon solar cell, wherein a conductive layer can be formed by curing the conductive paste or the conductive paste prepared by the preparation method of the conductive paste, the conductive paste can be cured or crosslinked under certain conditions to form a three-dimensional network structure, conductive metal particles are dispersed in the conductive paste, and have a certain shaping effect on the conductive metal particles, so that a conductive agent can be tightly accumulated, the conductivity of the conductive paste is improved.

Drawings

Fig. 1 is a scanning electron microscope image of glass powder provided by an embodiment of the present invention.

Detailed Description

In order to make the technical problems, technical solutions and advantageous effects to be solved by the present application more clearly apparent, the present application is further described in detail below with reference to the embodiments. It should be understood that the specific embodiments described herein are merely illustrative of and not restrictive on the broad application.

In this application, the term "and/or" describes an association relationship of associated objects, which means that there may be three relationships, for example, a and/or B, which may mean: a is present alone, A and B are present simultaneously, and B is present alone. Wherein A and B can be singular or plural. The character "/" generally indicates that the former and latter associated objects are in an "or" relationship.

In the present application, "at least one" means one or more, "a plurality" means two or more. "at least one of the following" or similar expressions refer to any combination of these items, including any combination of the singular or plural items. For example, "at least one item(s) of a, b, or c," or "at least one item(s) of a, b, and c," may each represent: a, b, c, a-b (i.e. a and b), a-c, b-c, or a-b-c, wherein a, b, and c can be single or multiple respectively.

It should be understood that, in various embodiments of the present application, the sequence numbers of the above-mentioned processes do not mean the execution sequence, some or all of the steps may be executed in parallel or executed sequentially, and the execution sequence of each process should be determined by its function and inherent logic, and should not constitute any limitation to the implementation process of the embodiments of the present application.

The terminology used in the embodiments of the present application is for the purpose of describing particular embodiments only and is not intended to be limiting of the application. As used in the specification of the present application and the appended claims, the singular forms "a," "an," and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise.

The weight of the related components mentioned in the description of the embodiments of the present application may not only refer to the specific content of each component, but also represent the proportional relationship of the weight among the components, and therefore, the content of the related components is scaled up or down within the scope disclosed in the description of the embodiments of the present application as long as it is scaled up or down according to the description of the embodiments of the present application. Specifically, the mass described in the specification of the embodiments of the present application may be a mass unit known in the chemical industry field such as μ g, mg, g, kg, etc.

The terms first, second, etc. are used for descriptive purposes only and are used for distinguishing purposes such as substances from one another and are not to be construed as indicating or implying relative importance or implying any number of technical features indicated. For example, a first XX may also be referred to as a second XX, and similarly, a second XX may also be referred to as a first XX, without departing from the scope of regulations of this application. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature.

The technical scheme adopted by the application is as follows:

the first aspect of the embodiments of the present application provides a glass frit, which comprises the following raw material components in percentage by mass:

in a first aspect, the glass powder provided in the embodiment of the present application can provide some trace elements for the glass powder by adjusting the compound ratio of the components such as lead oxide, boron oxide, silicon dioxide, aluminum oxide, zinc oxide, nickel oxide or/and germanium oxide, cobalt-containing compound, etc., and the electrical properties of the glass powder are improved by adding special trace elements into the glass powder. In a second aspect, the cobalt-containing compound introduced into the glass powder in the embodiments of the present application can provide excellent static conductivity, can collect micro-current of active substances, can greatly reduce contact resistance when applied to an N-type crystalline silicon solar cell, and can improve adhesion between the glass powder and a crystalline silicon layer, and at the same time, the glass powder is prepared by matching germanium oxide or/and nickel oxide, and can synergistically reduce contact resistance in a system and improve photoelectric conversion efficiency, so that the crystalline silicon layer is etched less in an etching process, and has excellent contact performance with the crystalline silicon layer, and the open circuit voltage of the N-type crystalline silicon solar cell can be increased, so that the overall performance of the N-type crystalline silicon solar cell is improved.

In some embodiments, the glass material comprises 30-50% of lead oxide, 15-30% of boron oxide, 20-30% of silicon dioxide, 1-10% of aluminum oxide, 0.5-5% of zinc oxide, 0-5% of nickel oxide and 10-20% of cobalt-containing compound.

In some embodiments, the frit comprises 30-50% lead oxide; 15-30% of boron oxide, 20-30% of silicon dioxide, 1-10% of aluminum oxide, 0.5-5% of zinc oxide, 0-2% of germanium oxide and 10-20% of cobalt-containing compound.

In some embodiments, the frit comprises 30-50% lead oxide; 15-30% of boron oxide, 20-30% of silicon dioxide, 1-10% of aluminum oxide, 0.5-5% of zinc oxide, 0-7% of nickel oxide and germanium oxide and 10-20% of cobalt-containing compound.

In some embodiments, lead oxide 42%, boron oxide 16%, silicon dioxide 22%, aluminum oxide 2.5%, zinc oxide 3%, nickel oxide 2%, germanium oxide 0.5%, cobalt-containing compound 12%.

In some embodiments, the cobalt-containing compound comprises at least one of lithium cobaltate, sodium cobaltate, magnesium cobaltate, lead cobaltate. In the above, the cobalt-containing compound is a layered functional material. According to the embodiment of the application, the cobalt-containing compound introduced into the glass powder is a layered functional material, and can provide excellent static conductivity, collect micro-current of active substances, greatly reduce contact resistance and improve the adhesion capacity between the two, and in a system, the cobalt-containing compound and other components generate synergistic effect, so that the contact resistance can be further reduced, and the photoelectric conversion efficiency is improved.

In a second aspect of the embodiments of the present application, there is provided a method for preparing a frit, including the steps of:

s10, weighing the components according to the mass percentage of the raw materials contained in the glass frit;

and S20, mixing and melting the raw materials to obtain the glass frit.

The preparation method of the glass frit mainly comprises two steps. The first step, the sintering temperature of the glass frit in the paper can be reduced by weighing the components according to the mass percentage of the raw materials contained in the glass frit in the paper. The glass raw materials are mixed to obtain a highly dispersed glass raw material mixture, so that the subsequent forming treatment of the glass raw materials is facilitated. And secondly, mixing and melting the raw materials to form liquid glass frit, wherein the glass frit prepared by the glass frit preparation method has lower contact resistance and higher photoelectric conversion efficiency in a system.

In some embodiments, in step S20, the mixing process and the melting process are performed in a stepwise manner.

In some embodiments, the stepwise manner comprises the steps of:

step S21: carrying out preheating treatment, mixing treatment and first melting treatment on the oxides except the cobalt-containing compound to obtain a first melt;

step S22: and adding a cobalt-containing compound into the first melt, mixing, and performing second melting to obtain a second melt.

The application provides a step-by-step implementation mode which mainly comprises two steps. In the first step, oxides except cobalt-containing compounds are subjected to preheating treatment, mixing treatment, and first melting treatment to obtain a highly dispersed first melt. And secondly, adding a cobalt-containing compound into the first molten material for mixing treatment and second melting treatment to finally obtain liquid glass material. The preparation process of the glass material is implemented by adopting a step-by-step mode, so that the resource during melting can be saved, and the success of firing the glass material can be ensured.

In some embodiments, the temperature of the preheating treatment is 400 to 500 ℃ and the preheating time is 0.5 to 1 hour. In the above, the temperature of the first melting treatment is 900 to 950 ℃, and the holding time is 0.5 to 1 hour. In the above, the temperature of the second melting treatment is 1100 to 1150 ℃ melting, and the holding time is 0.5 to 1 hour.

In some embodiments, the method further comprises performing water quenching on the second melt, so that the second melt can be solidified to obtain glass particles, and performing grinding and classification on the glass particles to obtain glass frits with preset particle sizes for application in the conductive silver paste.

In a third aspect of the embodiments of the present application, there is provided a conductive paste including conductive metal particles, and further including a glass frit in the above-mentioned article or a glass frit prepared by the above-mentioned method for preparing a glass frit.

The conductive paste provided by the embodiment of the application can reduce the contact resistance of the conductive paste and improve the photoelectric conversion efficiency of the conductive paste through the synergistic effect of the conductive metal particles and the glass frit in the conductive paste. The conductive paste formed by compounding the glass frit and the conductive agent provided by the embodiment of the application has the conductive performance given by the conductive agent, so that the conductive layer is formed.

In some embodiments, the conductive paste further includes an organic vehicle, the conductive metal particles and the glass frit provided in the embodiments of the present application are compounded to form a conductive paste, the conductive metal particles endow the conductive paste with conductive properties, and after being mixed with the organic vehicle, the conductive paste is conveniently subjected to a coating process to form a conductive layer.

In some embodiments, the conductive metal includes aluminum powder and silver powder. The conductive metal provided by the embodiment of the application comprises the aluminum powder and the silver powder, the shunting and composite effects of the N-type solar cell can be reduced, the conductive paste is formed by compounding the conductive metal and the organic carrier, the aluminum powder and the silver powder endow the conductive paste with conductive performance, the aluminum powder and the silver powder are dispersed in the organic carrier, the viscosity of the paste can be adjusted, the printing of the material is facilitated, the conductive paste is conveniently coated to form a conductive layer, and in the subsequent sintering process, the glass material can reduce the glass transition temperature of the conductive paste and enhance the low-temperature silver melting capability of the glass. By adjusting the compounding ratio of the glass frit, the organic carrier, the aluminum powder and the silver powder, the open-circuit voltage Voc and the filling factor FF of the TOPCon battery can be further improved, the conversion efficiency of the solar battery is further improved, and the kilowatt-hour cost is reduced.

A fourth aspect of the embodiments of the present application provides a method for preparing conductive paste, including the following steps: and mixing the conductive metal particles and the glass frit to obtain the conductive paste.

According to the conductive paste formed by compounding the glass material and the conductive metal particles, the conductive agent endows the conductive paste with conductive performance, so that the conductive paste is conveniently subjected to coating treatment to form a conductive layer. The glass frit has low metal induced recombination, so that the open circuit voltage of the conductive paste is improved, and the conductive paste has excellent contact resistivity at a low sintering temperature. In addition, the cobalt-containing glass frit of the embodiment of the application also supports an ultrathin polysilicon layer, has higher adhesion strength, and can reduce the contact resistance.

In a fifth aspect of the embodiments of the present application, an N-type TOPCon crystalline silicon solar cell is provided, which includes the conductive paste formed by curing treatment.

The cobalt-containing glass frit can be used for preparing the front silver-aluminum paste of the solar cell, wherein the solar cell comprises an N-type TOPCon crystalline silicon solar cell, and the open-circuit voltage of the solar cell can be improved. In a first aspect, the conductive paste in the above document can form a conductive layer by curing, the conductive paste can be cured or crosslinked under a certain condition to form a three-dimensional network structure, and the conductive metal particles are dispersed in the conductive paste, so that the conductive paste has a certain shaping effect on the conductive metal particles, can enable the conductive agent to be tightly stacked, and further improve the conductive performance of the conductive paste. In a second aspect, a cobalt-containing compound is introduced into the glass frit, which can provide excellent static conductivity, collect micro-current of the active material, thereby greatly reducing contact resistance and improving adhesion between the two. In the third aspect, the glass powder is prepared by matching with germanium oxide or/and nickel oxide, so that the contact resistance can be synergistically reduced in a system, the photoelectric conversion efficiency is improved, and the glass powder has excellent contact performance with a doped polycrystalline silicon layer.

In some embodiments, the particle size of the silver powder may be in the nanometer or micrometer range. For example, the silver powder may have a particle size of tens of nanometers to hundreds of nanometers, or several micrometers to tens of micrometers. Alternatively, the silver powder may be a mixture of two or more types of silver powders having different particle sizes.

In some embodiments, the organic vehicle imparts viscosity and rheological characteristics to the paste composition suitable for printing by mechanical mixing with the inorganic components of the composition for solar cell electrodes. The organic vehicle may be any typical organic vehicle for a composition for a solar cell electrode, and may include a binder resin, a solvent, and the like.

In order to make the details and operation of the above-mentioned embodiments of the present invention clearly understood by those skilled in the art, and to make the advanced performance of the glass frit and the manufacturing method, the conductive paste, the manufacturing method and the solar cell of the embodiments of the present invention remarkably manifest, the above-mentioned technical solutions are exemplified by a plurality of examples below.

Example 1

The embodiment provides a preparation method of glass powder, which comprises the following steps:

step S10: according to the weight percentage: 41 percent of lead oxide, 18 percent of boron oxide, 20 percent of silicon dioxide, 2.5 percent of aluminum oxide, 4 percent of zinc oxide, 2 percent of nickel oxide and 0.5 percent of germanium oxide are respectively weighed and prepared.

Step S20: the glass powder raw materials are placed in a mixer to be mixed evenly, a crucible carrying the glass powder raw materials is placed in a muffle furnace to be preheated for 0.5 hour at 500 ℃, then the temperature is raised to 950 ℃ to be melted, and the temperature is kept for 0.5 hour.

Step S30: then adding 12% of cobalt-containing compound, wherein the cobalt-containing compound comprises 8% of lithium cobaltate and 4% of sodium cobaltate, heating to 1150 ℃ for melting, and keeping the temperature for 0.5 hour.

Step S40: and (3) performing water quenching on the glass liquid by using deionized water, and placing the water-quenched glass slag into a jet mill for crushing, wherein the cobalt-containing glass material is used for the silver-aluminum paste of the N-type crystalline silicon solar cell.

Example 2

step S10: according to the weight percentage: 42 percent of lead oxide, 16 percent of boron oxide, 22 percent of silicon dioxide, 2.5 percent of aluminum oxide, 3 percent of zinc oxide and 2.5 percent of nickel oxide are respectively weighed and prepared.

Step S20: and (2) putting the glass powder raw materials into a mixer for uniform mixing, putting a crucible carrying the glass powder raw materials into a muffle furnace for preheating for 0.5 hour at 500 ℃, then heating to 950 ℃ for melting, and preserving heat for 0.5 hour.

Step S30: then adding 12% of cobalt-containing compound, wherein the cobalt-containing compound comprises 4% of lithium cobaltate and 8% of magnesium cobaltate, heating to 1150 ℃ for melting, and keeping the temperature for 0.5 hour.

Step S40: and (3) quenching the glass liquid with deionized water, and crushing the water-quenched glass slag in a jet mill to obtain the cobalt-containing glass material for the silver-aluminum paste of the N-type crystalline silicon solar cell.

Example 3

step S10: according to the weight percentage: 42% of lead oxide, 16% of boron oxide, 22% of silicon dioxide, 2.5% of aluminum oxide, 3% of zinc oxide, 2% of nickel oxide and 0.5% of germanium oxide are respectively weighed and prepared.

Step S30: then adding 12% of cobalt-containing compound, wherein the cobalt-containing compound comprises 10% of lead cobaltate and 2% of magnesium cobaltate, heating to 1150 ℃ for melting, and keeping the temperature for 0.5 hour.

Example 4

step S10: according to the weight percentage: 42% lead oxide, 16% boron oxide, 22% silicon dioxide, 2.5% aluminum oxide, 3% zinc oxide, 2.5% germanium oxide were weighed and prepared, respectively.

Step S30: then adding 12% cobalt compound, wherein the cobalt compound comprises 5% magnesium cobaltate and 7% sodium cobaltate, heating to 1150 ℃ for melting, and keeping the temperature for 0.5 hour.

Example 5

step S10: according to the weight percentage: 45% of lead oxide, 16% of boron oxide, 21% of silicon dioxide, 2.5% of aluminum oxide, 1% of zinc oxide, 2% of nickel oxide and 0.5% of germanium oxide are respectively weighed and prepared.

Step S30: then adding 12% of cobalt-containing compound, wherein the cobalt-containing compound comprises 9% of sodium cobaltate and 3% of lead cobaltate, heating to 1150 ℃ for melting, and keeping the temperature for 0.5 hour.

Example 6

The embodiment provides a silver paste, which comprises the following components in percentage by mass:

example 7

example 8

example 9

example 10

comparative example 1

The comparative example provides a silver paste which comprises the following components in percentage by mass:

performance testing

Table 1 is the composition of the silver pastes in examples 6 to 9, as follows:

table 1 example of silver paste preparation

Mass ratio of

Example 6

Example 7

Example 8

Example 9

Example 10

Comparative example 1

Silver powder

86％

84％

83％

84％

85％

86％

Aluminum powder

2％

3％

2％

1％

2％

Glass powder

4％

5％

6％

5％

4％

Organic vehicle

8％

9％

10％

9％

8％

The silver pastes of examples 1 to 5 and comparative example 1 were printed on the front surface of the N-type crystalline silicon solar cell, and the electrical performance test was performed, and the results are shown in table 2.

TABLE 2 Electrical Properties of silver paste

In the silver pastes of the embodiments 1 to 5, the open circuit voltage of the N-type crystalline silicon solar cell is 0.7004 to 0.7072V, the Filling Factor (FF) is 81.39 to 81.72%, and the photoelectric conversion rate (Eta) is 24.19 to 24.35%. The glass powder provided by the embodiment of the application can provide some trace elements for the glass powder by adjusting the compound ratio of the components such as lead oxide, boron oxide, silicon dioxide, aluminum oxide, zinc oxide, nickel oxide or/and germanium oxide, cobalt-containing compounds and the like, and special trace elements are added into the glass powder to improve the electrical property of the glass powder. The cobalt-containing compound introduced into the glass powder in the embodiment of the application can provide excellent static conductive performance, can collect micro-current of active substances, is applied to an N-type crystalline silicon solar cell, can greatly reduce contact resistance, can improve the adhesion capacity between polycrystalline silicon layers and doped polycrystalline silicon layers, and meanwhile, glass powder is prepared by matching germanium oxide or/and nickel oxide together, the contact resistance can be reduced in a system in a synergetic manner, the photoelectric conversion efficiency and the open-circuit voltage are improved, and the overall performance of the N-type crystalline silicon solar cell is obviously improved.

Fig. 1 is a scanning electron microscope image of the glass powder obtained in example 1, which shows that the glass powder has uniform particle size and narrow distribution, and most of the modified glass powder has a particle size of 1.0 to 2.0 micrometers, can form a dense sintering structure, and is suitable for being used for selecting silver-aluminum paste on the front surface of an N-type solar cell.

The above description is only exemplary of the present application and should not be taken as limiting the present application, as any modification, equivalent replacement, or improvement made within the spirit and principle of the present application should be included in the protection scope of the present application.

Claims

1. The glass frit is characterized by comprising the following raw material components in percentage by mass:

2. the frit according to claim 1, wherein the cobalt-containing compound comprises at least one of lithium cobaltate, sodium cobaltate, magnesium cobaltate, and lead cobaltate.

3. The frit according to claim 1 or 2, wherein the cobalt-containing compound is a layered functional material.

4. The preparation method of the glass frit is characterized by comprising the following steps:

weighing the components according to the mass percentage of the raw materials contained in the glass frit according to any one of claims 1 to 3;

and mixing and melting the raw materials to obtain the glass frit.

5. The method of claim 4, wherein the mixing and melting steps are performed in a stepwise manner.

6. The method of preparing a frit according to claim 5, wherein the step-wise manner comprises the steps of:

carrying out preheating treatment, mixing treatment and first melting treatment on oxides except for cobalt-containing compounds to obtain a first melt;

and adding a cobalt-containing compound into the first melt, and mixing and carrying out second melting treatment to obtain a second melt.

7. The method of claim 6, wherein the pre-heating is performed at a temperature of 400 to 500 ℃ for 0.5 to 1 hour.

8. The method for producing a glass frit according to claim 6 or 7, wherein the temperature of the first melting process is 900 to 950 ℃ and the holding time is 0.5 to 1 hour.

9. The method for preparing the frit according to claim 8, wherein the second melting process is performed at a temperature of 1100 to 1150 ℃ for 0.5 to 1 hour.

10. An electroconductive paste comprising electroconductive metal particles and further comprising a glass frit according to claim 1 or 2 or a glass frit produced by the method of producing a glass frit according to any one of claims 4 to 9.

11. The electroconductive paste according to claim 10, further comprising an organic vehicle.

12. The electroconductive paste according to claim 10 or 11, wherein the electroconductive metal comprises aluminum powder and silver powder.

13. The preparation method of the conductive paste is characterized by comprising the following steps of: and mixing the glass material, the organic carrier, the metal silver powder and the metal aluminum powder to obtain the conductive paste.

14. An N-type topocon crystalline silicon solar cell, characterized in that, it comprises the conductive paste of any one of claims 10 to 12 formed by curing treatment.