CN118522820A

CN118522820A - Electrode structure, preparation method thereof, solar cell and photovoltaic module

Info

Publication number: CN118522820A
Application number: CN202311575640.0A
Authority: CN
Inventors: 沐俊应; 许思航; 侯少康; 孙士洋; 唐喜颜; 唐清; 叶枫; 羽贺孝裕; 方亮
Original assignee: Longi Green Energy Technology Co Ltd
Current assignee: Longi Green Energy Technology Co Ltd
Priority date: 2023-11-23
Filing date: 2023-11-23
Publication date: 2024-08-20

Abstract

The invention provides an electrode structure, a preparation method thereof, a solar cell and a photovoltaic module, and relates to the technical field of photovoltaics. The method comprises the following steps: forming a laminated structure on the battery body; from keeping away from the battery body, to the direction that is close to the battery body, the stacked structure includes in proper order: the patterning layer, the whole main conductive metal layer and the whole first metal modification layer; the patterning layer is discontinuously distributed on the main conductive metal layer, so that part of the main conductive metal layer is exposed; wet etching is carried out on the exposed main conductive metal layer by adopting a first etching liquid to form a patterned main conductive metal layer, and a part of the first metal modification layer is exposed; and carrying out wet etching on the exposed first metal modification layer by adopting a second etching liquid to form a patterned first metal modification layer, and exposing the battery body part. The two adjacent etching steps are not interrupted by the non-etching step, so that the cost is low, and the diffusion of metal ions into the battery body can be reduced.

Description

Electrode structure, preparation method thereof, solar cell and photovoltaic module

Technical Field

The invention relates to the technical field of photovoltaics, in particular to an electrode structure, a preparation method thereof, a solar cell and a photovoltaic module.

Background

The solar cell can convert solar energy into electric energy, and clean energy is utilized, so that the solar cell has wide application prospect. The electrode structure of the solar cell is mainly used for conducting and collecting carriers.

In the process of manufacturing the electrode of the solar cell, etching and the like are inevitably performed. However, in the existing method for manufacturing the electrode of the solar cell, etching steps are more, resulting in higher cost.

Disclosure of Invention

The invention provides an electrode structure, a preparation method thereof, a solar cell and a photovoltaic module, and aims to solve the problem of high cost caused by more etching steps in the existing preparation method of an electrode.

In a first aspect of the present invention, there is provided a method for manufacturing an electrode structure of a solar cell, comprising:

forming a laminated structure on the battery body; from keeping away from the battery body to being close to the direction of battery body, the stacked structure includes in proper order: the patterning layer, the whole main conductive metal layer and the whole first metal modification layer; the patterning layers are intermittently distributed on the main conductive metal layer, so that the main conductive metal layer is partially exposed;

Wet etching is carried out on the exposed main conductive metal layer by adopting a first etching liquid to form a patterned main conductive metal layer, and a part of the first metal modification layer is exposed; ;

And carrying out wet etching on the exposed first metal modification layer by adopting a second etching liquid to form a patterned first metal modification layer, and exposing the battery body part.

In the embodiment of the invention, the etching of the main conductive metal layer and the etching of the first metal modification layer are adjacent etching steps, no other non-etching step exists between the two adjacent etching steps, and the two adjacent etching steps are not interrupted by the non-etching step, so that the preparation of the electrode structure can be completed by only one etching device, and the cost can be reduced. For example, the electrode structure can be prepared by using only one etching device or etching machine and arranging the first etching liquid and the second etching liquid in different grooves. Meanwhile, most metal ions diffuse into the battery body to at least cause adverse effects such as recombination, and as the selected first etching liquid basically has no etching effect on the first metal modification layer, the first metal modification layer below the first etching liquid basically can keep a complete structure in the process of wet etching the main conductive metal layer, metal ions in the main conductive metal layer can be blocked or obstructed in the etching process, and the metal ions in the main conductive metal layer are prevented from diffusing into the battery body in the etching process as much as possible, so that the effects such as recombination can be reduced. After etching, the patterned first metal modification layer is still arranged between the patterned main conductive metal layer and the battery main body for blocking or blocking, so that metal ions in the main conductive metal layer can be prevented from diffusing into the battery main body as much as possible in the subsequent use process of the solar battery and the like, and the influence of recombination and the like can be reduced. And the main conductive metal layer has good stability due to the blocking or blocking effect of the first metal modification layer. In addition, the two adjacent etching steps adopt wet etching, and compared with other etching modes, the wet etching can reduce the cost, improve the reliability, and is suitable for mass production and the like.

Optionally, the forming a stacked structure on the battery body includes:

forming a whole first metal modification layer, a whole main conductive metal layer and a whole outer layer structure on the battery body in sequence;

and removing part of the outer layer structure by at least one of laser etching and photoetching so that the main conductive layer part of the whole layer is exposed to form the patterned layer.

Optionally, the forming a stacked structure on the battery body includes:

forming a whole first metal modification layer and a whole main conductive metal layer on the battery body in sequence;

and (3) preparing the graphical layer on the whole main conductive metal layer by adopting at least one of ink-jet printing, screen printing and gravure printing.

Optionally, the patterning layer includes: a patterned masking layer, and/or a patterned second metal finishing layer, the patterned masking layer being furthest from the battery body; the patterned mask layer comprises the following materials: TCO, and/or tin; the material of the patterned second metal finishing layer comprises: at least one of nickel, titanium and silver.

Optionally, the battery body includes: a TCO layer immediately adjacent to the first metal modification layer and an entire layer;

the method for performing wet etching on the exposed first metal modification layer by adopting the second etching liquid to form a patterned first metal modification layer and exposing the battery body part comprises the following steps:

And etching the exposed first metal modification layer by adopting an acidic etching solution to form a patterned first metal modification layer, exposing a part of the TCO layer, and etching the exposed TCO layer by adopting the acidic etching solution to form the patterned TCO layer.

Optionally, the patterning layer includes: a patterned masking layer, the patterned masking layer comprising a material comprising: TCO, and/or tin; the patterned mask layer is farthest from the battery body; etching the exposed first metal modification layer by using an acid etching solution to form a patterned first metal modification layer, exposing a part of the TCO layer, and etching the exposed TCO layer by using the acid etching solution to form a patterned TCO layer, wherein the etching step comprises the following steps:

And etching the exposed first metal modification layer by adopting the acid etching liquid to form a patterned first metal modification layer, exposing a part of the TCO layer, etching the exposed TCO layer by adopting the acid etching liquid to form a patterned TCO layer, and etching the patterned mask layer by adopting the acid etching liquid.

Optionally, the patterned layer only includes: a patterned mask layer; the method for performing wet etching on the exposed first metal modification layer by adopting the second etching liquid to form a patterned first metal modification layer and exposing the battery body part comprises the following steps:

Etching the exposed first metal modification layer by adopting the second etching liquid to form a patterned first metal modification layer, exposing the battery body part, and etching the patterned mask layer by adopting the second etching liquid to expose the patterned main conductive metal layer;

Electroplating to obtain a patterned second metal modification layer on the patterned main conductive metal layer; the material of the patterned second metal finishing layer comprises: at least one of nickel, titanium, silver and tin.

Optionally, the first etching solution includes: neutral etching liquid or alkaline etching liquid;

the second etching liquid comprises: and (3) an acidic etching solution.

Optionally, the shape of the laser spot used for the laser etching includes: one of square and round; the laser spot has a size of 20 to 60 microns.

In a second aspect of the present invention, there is provided an electrode structure of a solar cell, comprising:

The patterned first metal modification layer is arranged next to the battery body;

the patterned main conductive metal layer is positioned on one side of the patterned first metal modification layer far away from the battery body;

wherein the material of the patterned main conductive metal layer comprises: copper;

The patterned first metal finishing layer comprises: a tin layer; or a tin layer immediately adjacent to the patterned bulk conductive metal layer, and an aluminum layer between the tin layer and the cell body.

Optionally, the electrode structure further includes:

And the patterned second metal modification layer is positioned on one side of the patterned main conductive metal layer away from the patterned first metal modification layer.

Optionally, the material of the patterned second metal finishing layer includes: at least one of nickel, titanium, silver and tin.

Optionally, the thickness of the patterned main conductive metal layer is greater than the thickness of the patterned second metal modification layer, and the thickness of the patterned main conductive metal layer is greater than the thickness of the patterned first metal modification layer.

Optionally, the patterned main conductive metal layer has a single-layer or multi-layer structure;

And/or, the patterned first metal modification layer is of a single-layer or multi-layer structure;

And/or, the patterned second metal modification layer is in a single-layer or multi-layer structure.

Optionally, the thickness of the patterned second metal modification layer is 50nm to 150nm.

In a third aspect of the present invention, there is provided a solar cell comprising:

a cell body and an electrode structure of a solar cell as described in any of the preceding, located on at least one side of the cell body.

Optionally, the battery body includes: a patterned TCO layer is disposed adjacent to the electrode structure.

In a fourth aspect of the present invention, there is provided a photovoltaic module comprising: a plurality of any of the foregoing solar cells.

The electrode structure, the preparation method of the electrode structure, the solar cell and the photovoltaic module have the same or similar beneficial effects, and in order to avoid repetition as much as possible, the description is omitted here.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings that are needed in the description of the embodiments of the present invention will be briefly described below, it being obvious that the drawings in the following description are only some embodiments of the present invention, and that other drawings may be obtained according to these drawings without inventive effort for a person skilled in the art.

Fig. 1 to 4 are schematic views showing steps of manufacturing an electrode structure of a solar cell according to an embodiment of the present invention;

Fig. 5 to 7 are schematic views showing steps of manufacturing an electrode structure of another solar cell in the embodiment of the present invention;

Fig. 8 to 11 are schematic views showing steps of manufacturing an electrode structure of still another solar cell in the embodiment of the present invention.

Description of the drawings:

1-cell body, 11-TCO layer, 21-patterned layer or outer structure, 22-main conductive metal layer, 23-first metal finish, 211-mask layer, 212-second metal finish.

Detailed Description

The following description of the embodiments of the present invention will be made clearly and fully with reference to the accompanying drawings, in which it is evident that the embodiments described are some, but not all embodiments of the invention. All other embodiments, which can be made by those skilled in the art based on the embodiments of the invention without making any inventive effort, are intended to be within the scope of the invention.

The inventors found that in the existing method for preparing the electrode of the solar cell, the etching steps are more, and the main reason for the higher cost is that: non-etching steps are also inserted between some adjacent etching steps, so that the continuity of the etching steps is broken, however, different etching equipment is usually required for each discontinuous etching step, so that more etching equipment is required for the etching steps in the preparation process of the electrode, and the cost is high.

The invention provides a preparation method of an electrode structure of a solar cell, which is characterized in that the solar cell is distinguished from materials: crystalline silicon solar cells, perovskite solar cells, and the like, can be distinguished from the distribution position of the electrode structure: the solar cell may be a bifacial solar cell, a back contact solar cell, or the like, and the type of the solar cell or the like is not particularly limited. For example, the solar cell may be an HBC (back contact heterojunction solar cell). The solar cell may include: a battery body, and an electrode structure on at least one side of the battery body. The cell body may include a base and an emitter, the electrode structure for collecting and conducting charge carriers in the cell body. The preparation method can comprise the following steps.

Step 101, forming a laminated structure on a battery body; from keeping away from the battery body to being close to the direction of battery body, the stacked structure includes in proper order: the patterning layer, the whole main conductive metal layer and the whole first metal modification layer; the patterning layer is discontinuously distributed on the main conductive metal layer, so that the main conductive metal layer is partially exposed.

Fig. 1 to 4 are schematic views showing steps of manufacturing an electrode structure of a solar cell according to an embodiment of the present invention. Fig. 5 to 7 are schematic views showing steps of manufacturing an electrode structure of another solar cell in the embodiment of the present invention. Fig. 8 to 11 are schematic views showing steps of manufacturing an electrode structure of still another solar cell in the embodiment of the present invention.

A schematic of a laminated structure is shown with reference to fig. 2. In the figure, the laminated structure is located on a battery body 1. In the drawing, a broken line L indicates a direction from the battery body 1 to the battery body 1. From the direction away from the battery body 1 toward the direction close to the battery body 1, the laminated structure sequentially includes: a patterned layer 21, an integral layer of a bulk conductive metal layer 22 and an integral layer of a first metal finish layer 23. The patterned layer 21 is intermittently distributed on the main conductive metal layer 22, so that the main conductive metal layer 22 is partially exposed. The bulk conductive metal layer 22 herein refers to the portion of the electrode structure that is primarily used to collect and conduct charge carriers. The material of the main conductive metal layer 22 may be a base metal or the like which has good conductivity and low cost.

The patterned layer 21 is intermittently distributed on the main conductive metal layer 22, and the size, specific shape, and the like of the intermittent distribution are not limited.

Step 102, performing wet etching on the exposed main conductive metal layer by using a first etching solution to form a patterned main conductive metal layer, and exposing a part of the first metal modification layer.

Referring to fig. 3, the exposed main conductive metal layer 22 is wet etched using a first etching solution to form a patterned main conductive metal layer 22, and a portion of the first metal modification layer 23 is exposed. The composition of the first etching liquid used herein and the like are determined according to the materials of the main body conductive metal layer 22 and the first metal finish layer 23, so as to be able to etch away the main body conductive metal layer 22 without substantially having an etching effect on the first metal finish layer 23.

And 103, carrying out wet etching on the exposed first metal modification layer by adopting a second etching solution to form a patterned first metal modification layer, and exposing the battery body part.

The first etching liquid and the second etching liquid are different. Referring to fig. 4, the exposed first metal modification layer 23 is wet etched using a second etching solution to form a patterned first metal modification layer 23, and a portion of the battery body 1 is exposed. The composition of the second etching liquid and the like used herein are determined according to the materials of the main body conductive metal layer 22 and the first metal finish layer 23 so as to be able to etch away the first metal finish layer 23 without substantially affecting the main body conductive metal layer 22.

Compared with the prior art that the adjacent etching steps are interrupted in the preparation process of the electrode structure, so that the technical problem of high etching cost is caused, in the invention, the etching of the main conductive metal layer 22 and the etching of the first metal modification layer 23 are adjacent etching steps, there is no other non-etching step between the two adjacent etching steps, and the two adjacent etching steps are not interrupted by the non-etching step, so that the preparation of the electrode structure can be completed by only one etching device, and the cost can be reduced. For example, the electrode structure can be prepared by using only one etching device or etching machine and arranging the first etching liquid and the second etching liquid in different grooves. Meanwhile, most metal ions diffuse into the battery body to at least cause adverse effects such as recombination, and as the selected first etching solution has no etching effect on the first metal modification layer 23 basically, the first metal modification layer 23 below the first etching solution can keep a complete structure basically in the process of wet etching the main conductive metal layer 22, and metal ions in the main conductive metal layer 22 can be blocked or obstructed in the etching process, so that the metal ions in the main conductive metal layer 22 are prevented from diffusing into the battery body in the etching process as much as possible, and the effects such as recombination can be reduced. After etching, the patterned first metal modification layer 23 still exists between the patterned main conductive metal layer 22 and the battery body 1 for blocking or blocking, so that metal ions in the main conductive metal layer 22 can be prevented from diffusing into the battery body 1 as much as possible in the subsequent use of the solar cell and the like, and the influence of recombination and the like can be reduced. And, the main conductive metal layer 22 has good stability due to the above-mentioned blocking or blocking effect of the first metal modification layer 23. In addition, the two adjacent etching steps adopt wet etching, and compared with other etching modes, the wet etching can reduce the cost, improve the reliability, and is suitable for mass production and the like.

Optionally, referring to fig. 1, the foregoing step 101 may include: on the battery body 1, a whole first metal modification layer 23, a whole main conductive metal layer 22 and a whole outer layer structure 21 are sequentially formed, then, at least one of laser etching and photoetching etching can be adopted to remove part of the outer layer structure 21, so that part of the main conductive layer 22 of the whole layer is exposed to form the patterned layer 21, and the etching precision of the laser etching and the photoetching etching is high and the etching efficiency is high. The whole first metal modification layer 23, the whole main conductive metal layer 22 and the whole outer layer structure 21 can be formed by vacuum plating (such as PVD), electroplating, chemical plating, etc., for example, the whole first metal modification layer 23, the whole main conductive metal layer 22 and the whole outer layer structure 21 can be formed by vacuum plating, and the thickness uniformity of the film formed by vacuum plating is better, and a film structure with a thinner thickness can be obtained, thereby further reducing the cost.

Alternatively, the shape of the laser spot used in the laser etching herein may include: the size of the laser spot can be 20 micrometers (micrometers) to 60 micrometers, the imaging size formed by the laser spot is proper, and the formed electrode structure has good performance. For example, the laser spot size may be 20 μm, or 27 μm, or 32 μm, or 45 μm, or 51 μm, or 60 μm. Alternatively, the laser used in the laser etching may be a violet laser, which has good processing accuracy, and the like.

Optionally, the foregoing step 101 may include: a whole first metal modification layer 23 and a whole main conductive metal layer 22 are sequentially formed on the battery body 1, and then at least one of three modes of ink-jet printing, screen printing and gravure printing is adopted on the whole main conductive metal layer 22 to prepare the patterned layer 21, wherein the preparation modes of the patterned layer 21 are various. The whole main conductive metal layer 22 and the whole first metal modification layer 23 can be formed by vacuum plating (such as PVD), electroplating, chemical plating, etc., for example, the whole main conductive metal layer 22 and the whole first metal modification layer 23 can be formed by vacuum plating, and the thickness uniformity of the film formed by vacuum plating is better, and a film structure with a thinner thickness can be obtained, thereby further reducing the cost.

Alternatively, the patterning layer 21 may include: patterned masking layer 211, and/or patterned second metal trim layer 212, patterned masking layer 211 being furthest from the cell body. For example, in fig. 1 to 3, the patterned layer 21 includes: a patterned masking layer 211 and a patterned second metal finish 212, the patterned masking layer 211 being furthest from the cell body. As another example, fig. 5 to 7, the patterned layer 21 includes only: a patterned second metal finish 212. As another example, in fig. 8 to 10, the patterned layer 21 includes only: patterned masking layer 211. Patterned layer 21 is in a variety of forms. The material of the patterned mask layer 211 includes: TCO (transparent conductive material) and/or tin, the mask layer of the material is easy to etch by means of laser etching, photoetching and the like, and has high processing precision, high processing efficiency and good mask effect. The materials of the patterned second metal finish 212 include: at least one of nickel, titanium and silver, on one hand, the material is easy to be etched by means of laser etching, photoetching and the like, and has high processing precision and high processing efficiency. Referring to fig. 4, after the patterned mask layer 211 is removed, the patterned second metal modification layer 212 is the outermost structure, on the other hand, in the subsequent series welding process of forming the photovoltaic module by the solar cell, the second metal modification layer 212 made of the material has larger pulling-out force and better welding performance, so that the long-term reliability of the photovoltaic module is better, and furthermore, the second metal modification layer 212 made of the material has better environmental tolerance or better weather resistance, so that the patterned main conductive metal layer 22 can be fully protected, the stability of the main conductive metal layer is improved, and the long-term reliability of the photovoltaic module can also be improved.

The second metal modification layer 212 may be formed in a vacuum plating manner, for example, the thickness of the second metal modification layer may be about 50nm to 150nm, so that patterning by laser etching or photolithography etching is easy, and patterning accuracy and efficiency are high. Even though silver is selected as the material of the second metal modification layer 212, the second metal modification layer 212 has a relatively thin thickness, and mainly plays a role in improving the long-term reliability of the photovoltaic module, and has relatively low cost compared with the all-silver electrode. TCOs mentioned throughout may include: ITO, AZO, etc.

Alternatively, referring to fig. 1 to 11, the battery body 1 may include: next to the first metal finishing layer 23 and the entire TCO layer 11, the TCO layer 11 here can be subjected to suitable band matching etc. for the electrode structure and the cell body, and low temperature deposition etc. can be achieved. Referring to fig. 4 and 11, the foregoing step 103 may include: the exposed first metal modification layer 23 is etched by adopting an acid etching liquid to form a patterned first metal modification layer 23, the TCO layer 11 is partially exposed, the exposed TCO layer 11 is etched by adopting the acid etching liquid to form a patterned TCO layer 11, and the patterning of the TCO layer 11 and the patterning of the first metal modification layer 23 are formed in one step, so that the process steps are saved, the production efficiency is improved, and the production cost is reduced. The acidic etching solution herein can etch away the first metal finish layer 23 and the TCO layer 11 described above, but needs to have substantially no etching effect on the bulk conductive metal layer 22.

Alternatively, referring to fig. 3 or 10, the patterned layer 21 may include: a patterned mask layer 211, the patterned mask layer 211 comprising a material comprising: TCO and/or tin, the mask layer of the above-mentioned material is easy to carry out etching by modes such as laser etching, photoetching and the like, and the machining precision is high, the machining efficiency is high, and the mask effect is good. The patterned mask layer 211 is furthest from the cell body 1. The foregoing etching of the exposed first metal modification layer 23 with the acidic etching solution to form the patterned first metal modification layer 23 and expose a portion of the TCO layer 11, and the etching of the exposed TCO layer 11 with the acidic etching solution to form the patterned TCO layer 11 includes: the acid etching solution is adopted to etch the exposed first metal modification layer 11 to form a patterned first metal modification layer 11, the exposed TCO layer 11 is partially exposed, the acid etching solution is adopted to etch the exposed TCO layer 11 to form a patterned TCO layer 11, meanwhile, the acid etching solution etches away the patterned mask layer 211, namely the acid etching solution removes the patterned mask layer 211 once, the first metal modification layer 23 and the TCO layer 11 are subjected to patterned etching, and the patterning of the TCO layer 11, the patterning of the first metal modification layer 23 and the patterning of the patterned mask layer 211 are further formed in one step, so that the process steps are saved, the production efficiency is improved, and the production cost is reduced. The acidic etching solution herein may etch away the first metal finish layer 23, the TCO layer 11 and the patterned mask layer 211 described above, but needs to have substantially no etching effect on the bulk conductive metal layer 22. For example, the acidic etching liquid may be hydrochloric acid (HCl) or the like.

Alternatively, referring to fig. 8 to 11, the patterned layer 21 includes only: referring to fig. 10 and11, the patterned mask layer 211, the foregoing step 103 may include: the second etching solution is adopted to etch the exposed first metal modification layer 23 to form a patterned first metal modification layer 23, the battery body 1 is exposed partially, and the second etching solution etches away the patterned mask layer 211 to expose the patterned main conductive metal layer 22. The second etching solution is also capable of removing the patterned mask layer 211 and etching away the first metal finish layer 23, but has substantially no etching effect on the bulk conductive metal layer 22. Next, referring to fig. 4, a patterned second metal modification layer 212 is electroplated on the patterned main conductive metal layer 22, where the material of the patterned second metal modification layer 212 includes: at least one of nickel, titanium, silver and tin. In this case, the patterned bulk conductive metal layer 22 serves as a seed layer for electroplating, and the second metal finish layer 212 of the above-described material is, on the one hand, suitable for electroplating. Referring to fig. 4, the patterned second metal modification layer 212 is the outermost structure, on the other hand, in the subsequent series welding process of forming the photovoltaic module by the solar cell, the second metal modification layer 212 made of the material has larger pulling-out force and better welding performance, so that the long-term reliability of the photovoltaic module is better, and furthermore, the second metal modification layer 212 made of the material has better environmental tolerance or weather resistance, can fully protect the patterned main conductive metal layer 22, improve the stability thereof and improve the long-term reliability of the photovoltaic module.

Referring to fig. 8 to 11, the battery body 1 further includes: the exposed first metal modification layer 23 is etched by adopting the second etching solution to form the patterned first metal modification layer 23, and the patterned mask layer 211 is removed, and meanwhile, the second etching solution can also perform patterning treatment on the whole TCO layer 11 to form a patterned TCO layer, which is equivalent to combining a plurality of etching steps, and has high production efficiency and low cost.

Optionally, the foregoing first etching solution may include: a neutral etching liquid, or an alkaline etching liquid, the second etching liquid may include: the acid etching solution is further needed for the first metal modification layer 23 to be etched or removed, the main conductive metal layer 22 is neutral etching solution or alkaline etching solution is possibly etched or removed, in the process of etching the main conductive metal layer 22, the neutral etching solution or alkaline etching solution can not be used for etching the first metal modification layer 23 basically, the first metal modification layer 23 can keep a complete appearance basically, and metal ions of the main conductive metal layer 22 can be prevented from diffusing into the battery body 1 in the process of etching the main conductive metal layer 22. Meanwhile, in the process of etching the first metal modification layer 23, the acidic etching solution has no etching influence on the main conductive metal layer 22 basically. And under the condition that the laminated structure comprises the patterned mask layer 211 and the TCO layer 11 is included in the battery body, the patterned mask layer 211 can be removed by adopting the acid etching liquid, and the TCO layer 11 can be subjected to patterned etching, which is equivalent to combining a plurality of etching steps, and the production efficiency is high and the cost is low. For example, the acidic etching liquid herein may be hydrochloric acid, and the neutral etching liquid herein may include: ferric chloride solution (FeCl ₃), the alkaline solution here may include: ammonia alkaline solution, etc.

The present invention also provides an electrode structure of a solar cell, as shown in fig. 4 and 11, the electrode structure comprising: the patterned first metal modification layer 23 is disposed adjacent to the battery body 1, and the patterned main conductive metal layer 22 is disposed on a side of the patterned first metal modification layer 23 away from the battery body 1. In the electrode structure, the patterned first metal modification layer 23 can prevent metal ions in the patterned main conductive metal layer 22 from diffusing to the battery body 1, and can also improve the stability of the main conductive metal layer 22.

Optionally, the material of the patterned bulk conductive metal layer 22 includes: copper has good conductivity, is not noble metal, and has low cost. The patterned first metal finishing layer 23 includes: a tin layer; or a tin layer immediately adjacent to the patterned bulk conductive metal layer 22, and an aluminum layer between the tin layer and the cell body 1. On the one hand, the patterned first metal modification layer 23 of the material can sufficiently block or obstruct Cu ions in the patterned main body conductive metal layer 22 from diffusing to the battery body 1, and the contact resistance between the patterned first metal modification layer 23 of the material and the adjacent battery body 1 and the patterned main body conductive metal layer 22 is smaller, so that the contact resistance can be reduced. For example, in the case that the cell body 1 includes the TCO layer 11 adjacent to the electrode structure, the contact resistance between the patterned first metal modification layer 23 and the TCO layer 11 and the patterned main conductive metal layer 22 is smaller, so that the problem of high contact resistance between the patterned main conductive metal layer 22 and the TCO layer 11 can be improved. In addition, the patterned main conductive metal layer 22 of the above material may use a neutral etching solution, such as FeCl ₃, or an alkaline, such as an ammonia alkaline solution, for example, while the patterned first metal modification layer 23 of the above material may use an acidic etching solution, such as hydrochloric acid, for example, for etching the above material, and the etching effect on the other is small in any one of the etching processes, so that diffusion of Cu ions in the patterned main conductive metal layer 22 to the battery body 1 and damage to the electrode structure and the like in the etching process of the patterned main conductive metal layer 22 can be avoided as much as possible.

Optionally, referring to fig. 4, the electrode structure may further include: the patterned second metal modification layer 212 is located on a side of the patterned main conductive metal layer 22 away from the patterned first metal modification layer 11, and the patterned second metal modification layer 212 is further outside, so that the patterned main conductive metal layer 22 can be fully protected, and the stability of the patterned main conductive metal layer is improved.

Optionally, the material of the patterned second metal finish 212 includes: at least one of nickel, titanium, silver and tin, the second metal modification layer 212 is of an outermost structure, on one hand, the second metal modification layer 212 made of the material is large in pulling-out force and good in welding performance in the subsequent series welding process of the solar cell forming photovoltaic modules, so that the long-term reliability of the photovoltaic modules is better, on the other hand, the second metal modification layer 212 made of the material is better in environmental tolerance or weather resistance, the patterned main conductive metal layer 22 can be fully protected, the stability of the second metal modification layer is improved, and the long-term reliability of the photovoltaic modules can be improved. The second metal decorative layer 212 of the above material is also easy to form patterning and the like.

Optionally, the thickness of the patterned main conductive metal layer 22 is greater than the thickness of the patterned second metal modification layer 212, and the thickness of the patterned main conductive metal layer 22 is greater than the thickness of the patterned first metal modification layer 23, so that the patterned first metal modification layer 23 mainly has the effects of preventing metal ions in the patterned main conductive metal layer 22 from diffusing, reducing contact resistance, maintaining the stability of the patterned main conductive metal layer 22, the patterned second metal modification layer 212 can play a role in improving welding reliability and long-term reliability of the photovoltaic module, in the electrode structure, the patterned main conductive metal layer 22 mainly plays a role in collecting and conducting current carriers, the patterned main conductive metal layer 22 can adopt base metal and the like, and the cost can be reduced. The thickness difference between the patterned main conductive metal layer 22 and the patterned second metal finishing layer 212 is not limited. The thickness of the patterned main conductive metal layer 22 and the thickness of the patterned first metal finishing layer 23 are not particularly limited. The relationship between the thickness of the patterned first metal modification layer 23 and the patterned second metal modification layer 212 is not particularly limited.

Optionally, the patterned main conductive metal layer 22 has a single-layer or multi-layer structure, and/or the patterned first metal modification layer 23 has a single-layer or multi-layer structure, and/or the patterned second metal modification layer 212 has a single-layer or multi-layer structure, and the electrode structure has various structural forms.

Optionally, the thickness of the patterned second metal modification layer 212 is 50nm to 150nm, and the patterned second metal modification layer 212 with the thickness not only can greatly improve the welding reliability and the long-term reliability of the photovoltaic module, but also is easy to prepare and has lower cost. For example, the thickness of the patterned second metal modification layer 212 is 50nm, or 60nm, or 71nm, or 83nm, or 90nm, or 120nm, or 150nm.

The present invention also provides a solar cell, as shown in fig. 4 and 11, comprising: the battery body 1 and any of the foregoing electrode structures on at least one side of the battery body 1 may refer to the foregoing description, and in order to avoid repetition as much as possible, no description is repeated here.

Alternatively, as shown in fig. 4 and 11, the battery body 1 includes: the patterned TCO layer 11, which is disposed adjacent to the electrode structure, may also refer to the above related descriptions, and will not be repeated here to avoid repetition as much as possible.

The invention also provides a photovoltaic module comprising: a plurality of any one of the solar cells described above. The photovoltaic module may further include packaging adhesive films or the like on opposite sides of the solar cell.

In the application, the electrode structure, the preparation method of the electrode structure, the solar cell and the photovoltaic module can be referred to each other, and the related parts are abbreviated for avoiding repetition as far as possible and have the same or similar beneficial effects.

The application is further illustrated below in conjunction with specific examples.

Example 1

Referring to fig. 1, the battery body includes: the whole layer of TCO layer 11 adopts the vacuum coating mode to form the first metal modification layer 23 of whole layer, the main body conductive metal layer 22 of whole layer and the outer layer structure 21 of whole layer in proper order on TCO layer 11. The first metal modification layer 23 is a tin layer, and the main conductive metal layer 22 is a copper layer. The outer layer structure 21 includes: a second metal finish 212 adjacent to the bulk conductive metal layer 22, and a mask layer 211 remote from the cell body 1. The material of the mask layer 211 is tin, and/or TCO. The material of the second metal modification layer 212 is at least one of nickel, titanium and silver. The thickness of the second metal modification layer 212 is 80nm. The thickness of the first metal modification layer 23 is 100nm, and the thickness of the main body conductive metal layer 22 is 500nm. The thickness of the mask layer 211 is 30nm to 100nm.

Referring to fig. 2, an ultraviolet laser is used to perform laser etching on the entire mask layer 211 to form a patterned mask layer 211, so that a portion of the second metal modification layer 212 is exposed. And then continuing to adopt the laser to carry out laser etching on the exposed second metal modification layer 212 to form a patterned second metal modification layer 212, so that the part of the main conductive metal layer 22 is exposed.

Referring to fig. 3, the exposed bulk conductive metal layer 22 is wet etched using FeCl ₃, or an ammonia base solution, such that a portion of the first metal finish layer 23 is exposed.

Referring to fig. 4, the patterned mask layer 211 is removed by using a hydrochloric acid solution, and the exposed first metal modification layer 23 is etched, so that a portion of the TCO layer 11 is exposed, and the hydrochloric acid solution continues to etch the exposed TCO layer 11 to form the patterned TCO layer 11.

In embodiment 1, the electrode structure is formed as shown in fig. 4, and the main material in the electrode structure is copper, so that the cost is low. In this embodiment 1, the etching of the main conductive metal layer 22, the etching of the first metal modification layer 23, the removal of the patterned mask layer 211, and the patterning of the TCO layer 11 can be performed in one etching machine or etching equipment, so that the etching steps are fewer, the production cost is low, and the production efficiency is high.

In embodiment 1, the second metal modification layer 212 is easy to be etched by laser etching, photolithography etching, and the like, and has high processing precision and high processing efficiency. On the other hand, in the subsequent series welding process of forming the photovoltaic module by the solar cell, the pull-out force is larger, and the welding performance is better, so that the long-term reliability of the photovoltaic module is better, and furthermore, the second metal modification layer 212 made of the material has better environmental tolerance or weather resistance, can fully protect the patterned main conductive metal layer 22, improve the stability of the patterned main conductive metal layer, and also can improve the long-term reliability of the photovoltaic module. In the process of etching the main conductive metal layer 22, feCl ₃ or ammonia alkaline solution basically has no etching influence on the first metal modification layer 23, the first metal modification layer 23 basically can keep the appearance intact, the diffusion of Cu ions into the battery body 1 in the etching process can be avoided as far as possible, and in the formed final structure, the first metal modification layer 23 can still prevent the diffusion of Cu ions into the battery body 1, so that the stability of the main conductive metal layer 22 is improved. In addition, the contact resistance between the first metal modification layer 23 and the patterned main conductive metal layer 22 and the contact resistance between the first metal modification layer and the TCO layer 11 are both lower, so that the contact resistivity can be reduced. Meanwhile, the first metal modification layer 23 can prevent the oxygen in the TCO layer 11 from oxidizing the main conductive metal layer 22, so as to further improve the stability of the main conductive metal layer 22.

Example 2

Referring to fig. 5, the battery body includes: the whole layer of TCO layer 11 adopts the vacuum coating mode to form the first metal modification layer 23 of whole layer, the main body conductive metal layer 22 of whole layer and the outer layer structure 21 of whole layer in proper order on TCO layer 11. Wherein the first metal finishing layer 23 includes: a tin layer adjacent to the bulk conductive metal layer 22, and an aluminum layer between the tin layer and the TCO layer 11. The bulk conductive metal layer 22 is a copper layer. The outer layer structure 21 comprises only: a second metal finish 212. The material of the second metal modification layer 212 is at least one of nickel, titanium and silver. The thickness of the second metal modification layer 212 is 80nm. The thickness of the first metal modification layer 23 is 100nm, and the thickness of the main body conductive metal layer 22 is 500nm.

Referring to fig. 6, an ultraviolet laser is used to perform laser etching on the entire second metal modification layer 212 to form a patterned second metal modification layer 212, so that a portion of the bulk conductive metal layer 22 is exposed.

Referring to fig. 7, the exposed bulk conductive metal layer 22 is wet etched using FeCl ₃, or an ammonia base solution, such that a portion of the first metal finish layer 23 is exposed.

And etching the exposed first metal modification layer 23 by adopting hydrochloric acid solution to form a patterned first metal modification layer 23, so that the TCO layer 11 is partially exposed, and continuously etching the exposed TCO layer 11 by adopting the hydrochloric acid solution to form the patterned TCO layer 11.

In embodiment 2, the electrode structure is formed as shown in fig. 4, and the main material in the electrode structure is copper, so that the cost is low. In embodiment 2, the etching of the main conductive metal layer 22, the etching of the first metal modification layer 23, and the patterning of the TCO layer 11 can be performed in one etching machine or etching equipment, so that the etching steps are few, the production cost is low, and the production efficiency is high.

In embodiment 2, the same or similar advantages as those of embodiment 1 are obtained, and in order to avoid repetition as much as possible, the description thereof will be omitted.

Example 3

Referring to fig. 8, the battery body includes: the whole layer of TCO layer 11 adopts the vacuum coating mode to form the first metal modification layer 23 of whole layer, the main body conductive metal layer 22 of whole layer and the outer layer structure 21 of whole layer in proper order on TCO layer 11. Wherein the first metal finishing layer 23 includes: and a tin layer. The bulk conductive metal layer 22 is a copper layer. The outer layer structure 21 comprises only: mask layer 211. The material of the mask layer 211 is tin, and/or TCO. The thickness of the first metal modification layer 23 is 100nm, and the thickness of the main body conductive metal layer 22 is 500nm. The thickness of the mask layer 211 is 30nm to 100nm.

Referring to fig. 9, an ultraviolet laser is used to perform laser etching on the entire mask layer 211 to form a patterned mask layer 211, so that a portion of the bulk conductive metal layer 22 is exposed.

Referring to fig. 10, the exposed bulk conductive metal layer 22 is wet etched using FeCl ₃, or an ammonia alkaline solution, to form a patterned bulk conductive metal layer 22 and to expose a portion of the first metal finish layer 23.

Referring to fig. 11, the patterned mask layer 211 is removed by using a hydrochloric acid solution, so that the patterned main conductive metal layer 22 is exposed, and the exposed first metal modification layer 23 is etched, so that a portion of the TCO layer 11 is exposed, and the hydrochloric acid solution continues to etch the exposed TCO layer 11 to form the patterned TCO layer 11.

Then, the patterned main conductive metal layer 22 is used as a seed layer, and a second metal modification layer 212 is formed on the seed layer by electroplating, wherein the material of the second metal modification layer 212 is at least one of nickel, titanium, silver and tin.

In embodiment 3, the electrode structure is formed as shown in fig. 4, and the main material in the electrode structure is copper, so that the cost is low. In embodiment 3, for the etching of the main conductive metal layer 22 and the patterning of the TCO layer 11, the removal of the patterned mask layer 211 can be performed in one etching machine or etching equipment, so that the etching steps are few, the production cost is low, and the production efficiency is high.

In embodiment 3, the same or similar advantages as those of embodiment 1 are obtained, and in order to avoid repetition as much as possible, the description thereof will be omitted.

It should be noted that, for simplicity of description, the method embodiments are shown as a series of acts, but it should be understood by those skilled in the art that the embodiments are not limited by the order of acts, as some steps may occur in other orders or concurrently in accordance with the embodiments. Further, those skilled in the art will appreciate that the embodiments described in the specification are presently preferred, and that the acts are not necessarily all required in accordance with the embodiments of the application.

It should be noted that, in this document, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising one … …" does not exclude the presence of other like elements in a process, method, article, or apparatus that comprises the element.

The embodiments of the present invention have been described above with reference to the accompanying drawings, but the present invention is not limited to the above-described embodiments, which are merely illustrative and not restrictive, and many forms may be made by those having ordinary skill in the art without departing from the spirit of the present invention and the scope of the claims, which are to be protected by the present invention.

Claims

1. A method for manufacturing an electrode structure of a solar cell, comprising:

2. The method of manufacturing according to claim 1, wherein the forming a laminated structure on the battery body comprises:

3. The method of manufacturing according to claim 1, wherein the forming a laminated structure on the battery body comprises:

4. A method of manufacturing as claimed in any one of claims 1 to 3, wherein the patterned layer comprises: a patterned masking layer, and/or a patterned second metal finishing layer, the patterned masking layer being furthest from the battery body; the patterned mask layer comprises the following materials: TCO, and/or tin; the material of the patterned second metal finishing layer comprises: at least one of nickel, titanium and silver.

5. A production method according to any one of claims 1 to 3, wherein the battery body comprises: a TCO layer immediately adjacent to the first metal modification layer and an entire layer;

6. The method of manufacturing of claim 5, wherein the patterned layer comprises: a patterned masking layer, the patterned masking layer comprising a material comprising: TCO, and/or tin; the patterned mask layer is farthest from the battery body; etching the exposed first metal modification layer by using an acid etching solution to form a patterned first metal modification layer, exposing a part of the TCO layer, and etching the exposed TCO layer by using the acid etching solution to form a patterned TCO layer, wherein the etching step comprises the following steps:

7. A method of manufacture according to any one of claims 1 to 3, wherein the patterned layer comprises only: a patterned mask layer; the method for performing wet etching on the exposed first metal modification layer by adopting the second etching liquid to form a patterned first metal modification layer and exposing the battery body part comprises the following steps:

8. A method of manufacturing according to any one of claims 1 to 3, wherein the first etching liquid comprises: neutral etching liquid or alkaline etching liquid;

the second etching liquid comprises: and (3) an acidic etching solution.

9. An electrode structure of a solar cell, comprising:

wherein the material of the patterned main conductive metal layer comprises: copper; ;

10. The electrode structure of claim 9, further comprising:

11. The electrode structure of claim 10, wherein the material of the patterned second metal finish layer comprises: at least one of nickel, titanium, silver and tin.

12. The electrode structure of claim 10, wherein the patterned bulk conductive metal layer has a thickness greater than the thickness of the patterned second metal finish layer and the patterned bulk conductive metal layer has a thickness greater than the thickness of the patterned first metal finish layer.

13. The electrode structure of claim 10, wherein the patterned bulk conductive metal layer is a single-layer or multi-layer structure;

14. The electrode structure of any one of claims 10 to 13, wherein the thickness of the patterned second metal modification layer is 50nm to 150nm.

15. A solar cell, comprising:

A cell body, and an electrode structure of a solar cell as claimed in any one of claims 9 to 14 on at least one side of the cell body.

16. The solar cell of claim 15, wherein the cell body comprises: a patterned TCO layer is disposed adjacent to the electrode structure.

17. A photovoltaic module, comprising: a number of solar cells as claimed in claim 15 or 16.