阅读说明：本技术 一种太阳能电池电极的制备方法 (Preparation method of solar cell electrode ) 是由 殷志豪 彭颖杰 陈娜娜 高绪彬 潘克菲 姜锴 于 2021-09-07 设计创作，主要内容包括：本发明公开了一种太阳能电池电极的制备方法,包括以下步骤：在基底表面设置两层可分离的压印胶层；在压印胶层上制备预设图案的凹槽；将具有凹槽结构的胶层面贴附在太阳能电池片上,分离胶层,在电池表面形成预设图案的沟槽；在沟槽中填充银浆,固化并去除胶层,形成预设图案的银电极。通过在压印胶层上增加纳米银线层并结合上述方法,在HJT电池表面制作电极的同时增加纳米银线层。上述方法可通过对压印模板及胶层厚度的设计来控制电极的高宽比,降低栅线电极的宽度,增加电池片的光照面积以提高转化效率；较之传统丝网印刷工艺,该工艺减少了电极制作过程对电池片的机械损伤,降低了产品的不良率。(The invention discloses a preparation method of a solar cell electrode, which comprises the following steps: arranging two separable imprinting adhesive layers on the surface of a substrate; preparing a groove with a preset pattern on the imprinting adhesive layer; attaching the adhesive layer surface with the groove structure on the solar cell, separating the adhesive layer, and forming a groove with a preset pattern on the surface of the cell; and filling silver paste in the groove, solidifying and removing the adhesive layer to form a silver electrode with a preset pattern. By adding the nano silver wire layer on the imprinting adhesive layer and combining the method, the nano silver wire layer is added while the electrode is manufactured on the surface of the HJT battery. According to the method, the height-width ratio of the electrode can be controlled by designing the thickness of the imprinting template and the glue layer, the width of the grid line electrode is reduced, and the illumination area of the cell is increased so as to improve the conversion efficiency; compared with the traditional screen printing process, the process reduces the mechanical damage to the battery plate in the electrode manufacturing process and reduces the reject ratio of products.)

1. A preparation method of a solar cell electrode is characterized by comprising the following steps:

(1) arranging a first adhesive layer on a substrate, carrying out surface treatment on the first adhesive layer to increase the release force, and arranging a second adhesive layer on the first adhesive layer after treatment to obtain a composite multilayer material;

(2) preparing a groove with a preset pattern on the second adhesive layer of the composite multilayer material by using an imprinting template; the groove extends into the first adhesive layer;

(3) attaching a second adhesive layer surface of the composite multilayer material with the groove structure to the solar cell, and removing the first adhesive layer and the substrate to form a groove with a preset pattern on the surface of the cell;

(4) and filling silver paste in the groove, heating and curing, removing the second adhesive layer, and forming a silver electrode with a preset pattern on the surface of the cell.

2. The method for preparing the solar cell electrode according to claim 1, wherein in the step (1), the surface treatment is specifically: and treating the surface of the first adhesive layer by adopting plasma, fluorine coating or silicon coating release agent.

3. The method for preparing the solar cell electrode according to claim 1, wherein the second adhesive layer is made of polymethacrylate, polystyrene, polycarbonate, polyaryl methacrylate or polyaryl methacrylate; the thickness of the second adhesive layer is 30-2000 mu m.

4. The method as claimed in claim 1, wherein in the step (4), the temperature for heating and curing is 130-900 ℃, and the time for heating and curing is 15-90 min.

5. The method for preparing the electrode of the solar cell according to claim 1, wherein in the step (4), the aspect ratio of the silver electrode is 0.3-3.

6. A preparation method of an electrode of an HJT solar cell is characterized by comprising the following steps:

(1) arranging a first adhesive layer on a substrate, treating the surface of the first adhesive layer by adopting plasma, fluorine coating or silicon coating release agent, and arranging a second adhesive layer on the first adhesive layer after treatment to obtain a composite multilayer material; the second adhesive layer is thermosetting stamping adhesive or ultraviolet curing stamping adhesive;

(2) coating nano-silver ink on the second adhesive layer of the composite multilayer material to form a nano-silver layer, so as to obtain the conductive composite multilayer material;

(3) preparing a groove with a preset pattern on a nano silver wire layer of the conductive composite multilayer material by using an imprinting template; the groove penetrates through the second adhesive layer and extends into the first adhesive layer;

(4) attaching the surface of the nano-silver wire layer of the conductive composite multilayer material with the groove structure to a solar cell, removing the first adhesive layer and the substrate, and forming the nano-silver wire layer and a groove with a preset pattern on the surface of the cell;

(5) and filling silver paste in the groove, heating and curing, and forming a silver electrode with a preset pattern and a protective layer on the surface of the battery piece.

7. The method of claim 6, wherein the sheet resistance of the layer of nanosilver is 10-200 Ω/□; the transmittance of the nano silver wire layer is 95% -99.9%.

8. The method as claimed in claim 6, wherein the temperature for heating and curing in step (5) is 130-200 ℃, and the time for heating and curing is 20-60 min.

9. The method of claim 6, wherein the silver electrode in step (5) has an aspect ratio of 0.3 to 3.

10. The method of claim 6, wherein the protective layer has a transmittance of greater than 98%.

Technical Field

The invention relates to the technical field of photovoltaic cells, in particular to a preparation method of a solar cell electrode.

Background

The grid line electrode is an important component of the cell and is responsible for collecting and transporting current to the outside of the cell, and optical loss caused by the shading area of the electrode is one of main factors restricting the improvement of the efficiency of the solar cell. The thinner the grid line electrode on the surface of the solar cell is, the smaller the optical loss caused by electrode shielding is, but in the traditional process, a grid electrode is manufactured by printing photovoltaic silver paste on the surface of the cell in a screen printing mode, the width of the screen printing grid line has a certain limit due to the limitation of screen printing precision, and otherwise, the grid breaking phenomenon can occur. At present, the design width of grid lines is 35-45 mu m, which is close to a limit value, the height-width ratio is only about 0.3, and the improvement is difficult, so that the design width becomes an obstacle for restricting the efficiency of a solar cell. In addition, the silver paste process is screen printed to cause mechanical damage to the battery cell.

In contrast, new grid line electrode processing technologies are continuously available, for example, in the patent "preparation process of front electrode grid line of solar cell" (CN102709394B), a double-nozzle device is used to spray double-layer slurry on a silicon wafer to prepare the electrode grid line, and the aspect ratio of the obtained metal grid line is greater than 0.3. In a patent 'method for preparing a photovoltaic cell grid line electrode by soluble mask vacuum plating' (CN11090140B), a hollow mask vacuum coating mode is adopted to sputter a metal electrode on the surface of a cell piece, and the method has high requirements on instruments and equipment and high production cost and is not suitable for industrialization.

Disclosure of Invention

In order to solve the problems, the invention provides a preparation method of a solar cell electrode, which comprises the steps of manufacturing a groove on a glue layer according to a preset pattern by a nano-imprinting method, transferring an obtained glue mold to the surface of a solar cell, filling silver paste into the groove of the glue mold, and curing to manufacture the electrode; in addition, the invention also provides a preparation method of the HJT battery electrode, the nano-silver wire layer is coated on the imprinting adhesive layer before the die is imprinted, according to the preparation method, the nano-silver wire layer and the electrode are simultaneously prepared on the surface of the battery piece, and the cured high-transparency adhesive layer is used as a protective layer of the battery, so that the effects of cost reduction and efficiency improvement are achieved. In the preparation method, the height-width ratio of the electrode can be controlled by designing the thickness of the imprinting template and the glue layer, the width of the grid line electrode is reduced, and the illumination area of the cell is increased to improve the conversion efficiency.

The invention provides the following technical scheme:

the invention provides a preparation method of a solar cell electrode, which comprises the following steps:

(1) arranging a first adhesive layer on a substrate, carrying out surface treatment on the first adhesive layer to increase the release force, and arranging a second adhesive layer on the first adhesive layer after treatment to obtain a composite multilayer material;

(2) preparing a groove with a preset pattern on the second adhesive layer of the composite multilayer material by using an imprinting template; the groove extends into the first adhesive layer;

(3) attaching a second adhesive layer surface of the composite multilayer material with the groove structure to the solar cell, and removing the first adhesive layer and the substrate to form a groove with a preset pattern on the surface of the cell;

(4) and filling silver paste in the groove, heating and curing, removing the second adhesive layer, and forming a silver electrode with a preset pattern on the surface of the cell.

Further, in the step (1), the surface treatment specifically comprises: and treating the surface of the first adhesive layer by adopting plasma, fluorine coating or silicon coating release agent to form ultra-light and stable release force between the first adhesive layer and the second adhesive layer, so that the subsequent separation is facilitated.

Further, the first adhesive layer is thermosetting or ultraviolet curing type stamping adhesive; the thickness of the first adhesive layer is 5-200 μm.

Further, the second adhesive layer is a thermoplastic imprinting adhesive and is selected from one of polymethacrylate, polystyrene, polycarbonate, polyaryl methacrylate and polyaryl methacrylate.

Further, the thickness of the second glue layer is 30-2000 μm.

Further, in the step (4), the temperature for heating and curing is 130-900 ℃, and the time for heating and curing is 15-90 min.

Further, in the step (4), the silver paste is a low-temperature silver paste or a high-temperature silver paste; when the silver paste is low-temperature silver paste, heating and curing the silver paste, and stripping the silver paste in a state that the second adhesive layer is softened; when the silver paste is high-temperature silver paste, the silver paste is heated to 150-.

Further, in the step (4), the aspect ratio of the silver electrode is 0.3-3.

The invention provides a preparation method of an electrode of an HJT solar cell, which comprises the following steps:

(1) arranging a first adhesive layer on a substrate, treating the surface of the first adhesive layer by adopting plasma, fluorine coating or silicon coating release agent, and arranging a second adhesive layer on the first adhesive layer after treatment to obtain a composite multilayer material; the second adhesive layer is thermosetting stamping adhesive or ultraviolet curing stamping adhesive;

(2) coating nano-silver ink on the second adhesive layer of the composite multilayer material to form a nano-silver layer, so as to obtain the conductive composite multilayer material;

(3) preparing a groove with a preset pattern on a nano silver wire layer of the conductive composite multilayer material by using an imprinting template; the groove penetrates through the second adhesive layer and extends into the first adhesive layer;

(4) attaching the surface of the nano-silver wire layer of the conductive composite multilayer material with the groove structure to a solar cell, removing the first adhesive layer and the substrate, and forming the nano-silver wire layer and a groove with a preset pattern on the surface of the cell;

(5) and filling silver paste in the groove, heating and curing, and forming a silver electrode with a preset pattern and a protective layer on the surface of the battery piece.

Further, the second adhesive layer is thermosetting type stamping adhesive or ultraviolet curing type stamping adhesive.

Further, the thickness of the first glue layer is 5-200 μm; the thickness of the second adhesive layer is 30-2000 mu m.

Further, the thickness of the nano silver wire layer is 10-100 nm; the transmittance of the nano silver wire layer is 95% -99.9%.

Further, the sheet resistance of the nano silver wire layer is 10-200 omega/□.

Further, in the step (5), the temperature for heating and curing is 130-200 ℃, and the time for heating and curing is 20-60 min.

Further, in the step (5), the aspect ratio of the silver electrode is 0.3-3.

Further, a transparent protective layer is formed on the surface of the battery after the second adhesive layer is cured, and the transmittance of the protective layer is greater than 98%.

Compared with the prior art, the invention has the beneficial effects that:

1. manufacturing a groove on the adhesive layer according to a preset pattern by a nanoimprint method, transferring the obtained rubber mold to the surface of the solar cell, filling silver paste into the groove of the rubber mold, and curing to manufacture an electrode; the preparation method is simple and low in cost, the height-width ratio of the electrode can be controlled by designing the thickness of the imprinting template and the glue layer, the width of the grid line is reduced, the illumination area of the cell is increased, and therefore the photoelectric conversion efficiency is improved.

2. According to the preparation method, the nano silver wire layer and the protective layer are added while the silver electrode is prepared on the surface of the HJT battery, and the nano silver wire layer is tightly connected with the transparent conductive oxide film and the silver electrode on the surface of the HJT battery, so that the contact resistance between the silver electrode and the transparent conductive oxide film can be reduced, the conductive performance is met, the use amount of the transparent conductive oxide film can be reduced, and the effects of cost reduction and efficiency improvement are achieved; the glue mold for preparing the silver electrode is solidified to form a transparent protective layer on the surface of the battery, so that the adhesion between the silver electrode and the battery can be improved, and the battery can be protected to a certain extent.

Drawings

FIG. 1 is a flow chart of a process for preparing a solar cell electrode;

FIG. 2 is a flow chart of the process for preparing an electrode of an HJT cell.

Detailed Description

The present invention is further described below in conjunction with the following figures and specific examples so that those skilled in the art may better understand the present invention and practice it, but the examples are not intended to limit the present invention.

Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. The terminology used in the description of the invention herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. As used herein, the term "and/or" includes any and all combinations of one or more of the associated listed items.

The experimental methods used in the following examples are conventional methods unless otherwise specified, and materials, reagents and the like used therein are commercially available without otherwise specified.

Example 1: electrode made on surface of HJT battery

A method for preparing a solar cell electrode is shown in fig. 1, and specifically comprises the following steps:

arranging a layer of acrylic resin on the surface of a polyethylene terephthalate (PET) substrate, and then arranging a layer of polymethyl methacrylate (PMMA) after coating a layer of silicon release agent on the surface of the acrylic resin;

heating to soften PMMA, and then utilizing an imprinting template to imprint and penetrate into the acrylic resin layer on the surface of the PMMA to prepare a groove with a preset pattern;

inverting the substrate, attaching the PMMA surface to a transparent conductive oxide film (ITO in the embodiment) of the HJT battery, stripping the acrylic resin layer and the substrate, and forming a groove with a preset pattern on the surface of the battery;

and fourthly, filling silver paste in the groove, heating at 180 ℃ for 20min, stripping PMMA, and solidifying the silver paste on the surface of the battery to form an electrode with a preset pattern.

By adjusting the shape of the imprinting template and the thickness of the second glue layer, HJT cells with electrodes with different aspect ratios are prepared:

sample a 1: the line height is 30 μm, the line width is 25 μm;

sample a 2: the line height was 40 μm and the line width was 40 μm.

Example 2: method for manufacturing nano silver layer, electrode and protective layer on surface of HJT battery

A method for preparing an electrode of an HJT solar cell is shown in fig. 2, and specifically comprises the following steps:

firstly, arranging a first layer of acrylic resin on the surface of a PET substrate, coating a layer of silicon release agent on the surface of the first layer of acrylic resin, and then arranging a second layer of acrylic resin;

coating nano silver ink on the upper surface of the second layer of acrylic resin to form a nano silver layer;

thirdly, utilizing a stamping template to stamp and penetrate into the first acrylic resin layer on the nano silver line layer to prepare a groove with a preset pattern;

the substrate is inverted, the nano silver wire layer is attached to a transparent conductive oxide film (ITO in the embodiment) of the HJT battery, the first acrylic resin layer and the substrate are stripped, and a groove with a preset pattern is formed on the surface of the battery;

filling silver paste in the groove, heating at 180 ℃ for 20min, solidifying the silver paste to form an electrode with a preset pattern on the surface of the battery, solidifying acrylic resin to form a transparent protective layer on the surface of the battery, and embedding the nano silver wire layer between the ITO film and the protective layer.

By adjusting the content of the nano-silver wires in the nano-silver wire ink, the HJT battery with a protective layer, nano-silver wire layers with different conductivities and electrodes is prepared:

sample B1: the sheet resistance of the nano silver wire layer is 40 omega/□, the wire height is 40 mu m, and the wire width is 40 mu m;

sample B2: the sheet resistance of the nano silver wire layer is 60 omega/□, the wire height is 40 mu m, and the wire width is 40 mu m;

sample B3: the sheet resistance of the nano silver layer is 80 omega/□, the line height is 40 mu m, and the line width is 40 mu m;

sample B4: the sheet resistance of the nano-silver layer was 100 Ω/□, the line height was 40 μm, and the line width was 40 μm.

Comparative example: method for manufacturing HJT battery electrode by screen printing method

Printing silver paste (the same as the silver paste used in the embodiments 1 and 2) on the surface of the HJT battery in a screen printing mode, heating at 180 ℃ for 20min, and curing to obtain a silver paste electrode; samples of HJT cells with different aspect ratio electrodes were as follows:

comparative example 1: the line height is 15 μm, and the line width is 50 μm;

comparative example 2: the line height was 12 μm and the line width was 40 μm.

Comparison of Performance

The photoelectric properties of the HJT cells prepared by the different electrode preparation methods in example 1 and comparative example were compared, and the results are shown in table 1 below:

table 1 comparison of photoelectric properties of HJT cells in example 1 and comparative examples

From the results, under the condition of the same silver paste usage amount, the height-width ratio is large, the shading is less, and the conversion efficiency is improved; under the condition that the electrode line width is the same, the higher the aspect ratio is, the lower the resistance is, and the higher the conversion efficiency is.

The HJT cell with the silver layer in example 2 was compared to sample a2 without the silver nanowire layer in example 1 and the photovoltaic performance of comparative example 2, with the results shown in table 2 below:

TABLE 2 comparison of photoelectric Properties of different HJT cell samples

Based on the conversion efficiency of comparative example 2, the conversion efficiency of samples B1-B4 on the layer of the increased nano-silver wire is increased by an amount higher than that of sample a2 on the layer of the increased height-width ratio, because the increase of the layer of the nano-silver wire reduces the contact resistance between the electrode and the transparent conductive layer, and further improves the conversion efficiency of the cell, but with the increase of the content of the nano-silver wire in the layer of the nano-silver wire, the sheet resistance and the transmittance of the layer of the nano-silver wire are reduced, and the conductivity is improved while the transmittance of light is affected, so the content of the nano-silver wire in the layer of the nano-silver wire needs to be reasonably controlled.

The above-mentioned embodiments are merely preferred embodiments for fully illustrating the present invention, and the scope of the present invention is not limited thereto. The equivalent substitution or change made by the technical personnel in the technical field on the basis of the invention is all within the protection scope of the invention. The protection scope of the invention is subject to the claims.