CN118335813A

CN118335813A - Solar cell, preparation method, photovoltaic cell and laminated cell

Info

Publication number: CN118335813A
Application number: CN202410397863.0A
Authority: CN
Inventors: 余丁; 赵世杰; 张婷婷; 李文琪; 杨洁; 郑霈霆; 张昕宇
Original assignee: Jingke Energy Shangrao Co ltd; Jinko Solar Co Ltd
Current assignee: Jingke Energy Shangrao Co ltd; Jinko Solar Co Ltd
Priority date: 2024-04-03
Filing date: 2024-04-03
Publication date: 2024-07-12

Abstract

The application relates to the technical field of solar cells, in particular to a solar cell, a preparation method, a photovoltaic cell and a laminated cell. The solar cell includes: a substrate; a doped conductive layer positioned on one side of the substrate; the first electrode is positioned on one side of the doped conductive layer far away from the substrate and is electrically connected with the doped conductive layer; a glass layer positioned between the first electrode and the doped conductive layer; a plurality of first contact areas and/or a plurality of second contact areas are arranged in the glass layer; the first contact area and the second contact area are internally provided with a plurality of conductive particles, the adjacent conductive particles are not connected with each other, and the distance between the adjacent conductive particles is less than or equal to 10nm; the conductive particles in the first contact region are of a different type than the conductive particles in the second contact region. According to the application, electrons can be conducted between conductive particles through quantum tunneling effect, so that electron transmission is realized, and further the photo-generated current leading-out efficiency of the solar cell is improved.

Description

Solar cell, preparation method, photovoltaic cell and laminated cell

Technical Field

The application relates to the technical field of solar cells, in particular to a solar cell, a preparation method, a photovoltaic cell and a laminated cell.

Background

Currently, the technology and product of the mainstream passivation contact battery (TOPCon) have the passivation contact structure comprising a tunneling oxide layer and a doped polysilicon layer, wherein the thickness of the doped polysilicon layer is generally 80-200 μm, the metal electrode is in contact with the doped polysilicon layer, the metal electrode is generally prepared by screen printing metal silver paste, and the metal electrode and the doped polysilicon layer form ohmic contact.

In the prior conventional TOPCon battery back metal contact area, the size of silver particles is generally larger, the doped polysilicon layer is thicker to ensure that good ohmic contact is formed with the silver particles, so that the polysilicon layer has serious parasitic absorption, the loss of short-circuit current of the battery is caused, and the photoelectric conversion efficiency and the power generation double-sided rate of the battery are reduced.

Disclosure of Invention

The application provides a solar cell, a preparation method photovoltaic cell and a laminated cell, and aims to realize the thinning of a doped conductive layer, simultaneously meet the transmission of current, improve the open-circuit voltage, short-circuit current and filling factor of the solar cell and improve the lead-out efficiency of photo-generated current.

The present application provides in a first aspect a solar cell comprising:

a substrate;

A doped conductive layer positioned on one side of the substrate;

The first electrode is positioned on one side of the doped conductive layer far away from the substrate and is electrically connected with the doped conductive layer;

a glass layer between the first electrode and the doped conductive layer;

A plurality of first contact areas and/or a plurality of second contact areas are arranged in the glass layer;

The first contact area and the second contact area are internally provided with a plurality of conductive particles, the adjacent conductive particles are not connected with each other, and the distance between the adjacent conductive particles is less than or equal to 10nm;

The conductive particles in the first contact region are of a different type than the conductive particles in the second contact region.

In one possible design, the first electrode has a spacing of 10nm or less from adjacent conductive particles, and the doped conductive layer has a spacing of 10nm or less from adjacent conductive particles.

In one possible design, the conductive particles include first conductive particles, second conductive particles, and third conductive particles.

In one possible design, a plurality of the first conductive particles and a plurality of the second conductive particles are disposed within the first contact region;

A plurality of first conductive particles are positioned at the interface of the glass layer and the doped conductive layer and are in contact with the doped conductive layer;

The second conductive particles are positioned in the glass layer, and the distance between the first electrode and the adjacent second conductive particles is less than or equal to 10nm.

In one possible design, a plurality of the first conductive particles, a plurality of the second conductive particles, and a third conductive particle are disposed within the second contact region;

The second conductive particles are positioned in the glass layer, and the distance between the first electrode and the adjacent second conductive particles is less than or equal to 10nm;

The third conductive particles are in a crotch shape, and a plurality of second conductive particles are distributed around the third conductive particles.

In one possible design, the third conductive particles have opposite first and second ends along the thickness direction of the solar cell;

the first end is positioned in the glass layer and extends towards the direction of the doped conductive layer, and the distance between the first end and the adjacent first conductive particles is less than or equal to 10nm;

The second end is in contact with the first electrode.

the first end is positioned at the interface of the glass layer and the doped conductive layer;

the second end is positioned in the glass layer and extends towards the first electrode, and the distance between the second end and the first electrode is less than or equal to 10nm.

the first end is positioned at the interface of the glass layer and the doped conductive layer, and the second end is in contact with the first electrode.

In one possible design, the first conductive particles have a size of 20nm or less.

In one possible design, the second conductive particles have a size of 10nm or less.

In one possible design, the third conductive particles have a size of 20nm to 150nm.

The second aspect of the application provides a method for manufacturing a solar cell, the method comprising:

Forming a doped conductive layer on the surface of the substrate;

forming a first passivation layer on the surface of the doped conductive layer;

printing metal paste on the surface of the first passivation layer far away from the doped conductive layer;

carrying out a sintering process on the metal slurry to form a first electrode, a glass layer positioned between the first electrode and the doped conductive layer and a plurality of first contact areas positioned in the glass layer, wherein the first contact areas are internally provided with a plurality of conductive particles;

And carrying out laser processing on the first contact region, wherein part of the conductive particles can be crosslinked, so that part of the first contact region is converted into a second contact region.

In one possible design, a plurality of first conductive particles and a plurality of second conductive particles are disposed within the first contact region formed through the sintering process;

A plurality of the second conductive particles are located within the glass layer.

In one possible design, the method further comprises:

The temperature of the sintering process is 650-800 ℃.

In one possible design, the method of forming the second contact region under the influence of the laser process includes:

in a portion of the first contact region, a portion of the second conductive particles melts with surrounding glass bodies, cross-linking the second conductive particles, converting into third conductive particles, to form the second contact region with the first conductive particles, the second conductive particles, and the third conductive particles.

part of the first contact region, part of the second conductive particles and part of the first conductive particles are melted with surrounding glass body, so that the second conductive particles and the first conductive particles are crosslinked and converted into third conductive particles, and the second contact region with the first conductive particles, the second conductive particles and the third conductive particles is formed.

In one possible design, the second surface of the substrate is provided with a second electrode, and the method further comprises, prior to performing the laser process:

and externally connecting a reverse bias voltage between the first electrode and the second electrode to form an electric field which is directed to the second electrode by the first electrode.

In one possible design, the external reverse bias voltage between the first electrode and the second electrode is 10V-20V;

The incident light source of the laser process is monochromatic laser or mixed laser with the wavelength of 632 nm-1550 nm;

the spot size of the laser process is 0.005mm ²～0.01mm²;

the speed of the laser process is 50000 mm/s-60000 mm/s;

the density of the photo-generated current generated by the irradiation of the laser process is 20000A/cm ²～45000A/cm².

The third aspect of the application provides a photovoltaic module, which comprises a first cover plate, a first adhesive film, a battery string, a second adhesive film and a second cover plate which are arranged in a stacked manner;

The battery string comprises a plurality of electrically connected solar batteries, wherein the solar batteries are the solar batteries.

A third aspect of the present application provides a laminated battery comprising:

a bottom cell which is a solar cell as described above;

The top battery is one of a perovskite battery, a cadmium telluride solar battery, a copper indium gallium selenium solar battery or a gallium arsenide solar battery;

And the middle connecting layer is connected between the bottom battery and the top battery.

According to the application, the first conductive particle size and the second conductive particle size are reduced, and simultaneously, the distances between the adjacent first conductive particles and the second conductive particles, between the adjacent second conductive particles and between the first electrode and the adjacent second conductive particles are correspondingly reduced, so that the etching damage to the doped conductive layer is reduced, the thinning of the doped conductive layer is realized, and meanwhile, the transmission of current is also satisfied. In addition, the third conductive particles are formed through the crosslinking of the second conductive particles or the crosslinking of the second conductive particles and the first conductive particles, so that a conductive path is further increased, the open-circuit voltage, the short-circuit current and the filling factor of the solar cell are improved, and the efficiency of exporting the effective photo-generated current is further improved.

It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the application as claimed.

Drawings

FIG. 1 is a schematic diagram of a prior art passivation contact structure;

Fig. 2 is a schematic structural diagram of a solar cell according to the present application;

FIG. 3 is a schematic view of a passivation contact structure according to an embodiment of the present application;

FIG. 4 is a schematic view of a passivation contact structure according to another embodiment of the present application;

FIG. 5 is a schematic view of a first contact area provided by the present application;

FIG. 6 is a SEM image of a first contact area provided by the present application;

FIG. 7 is a schematic view of a second contact region according to an embodiment of the present application;

FIG. 8 is a SEM image of a second contact area provided by the present application;

FIG. 9 is a schematic view of a second contact region provided in accordance with another embodiment of the present application;

FIG. 10 is a schematic view of a second contact region provided in accordance with another embodiment of the present application;

FIG. 11 is a schematic view of a second contact region provided in another embodiment of the present application;

FIG. 12 is a schematic view of a passivation contact structure according to another embodiment of the present application;

FIG. 13 is a schematic view of a passivation contact structure according to another embodiment of the present application;

fig. 14 is a process flow diagram for preparing a passivated contact structure.

Reference numerals:

1' -solar cell;

11' -base layer;

a 12' -tunneling layer;

A 13' -doped polysilicon layer;

A 14' -surface passivation layer;

15' -metal electrode;

A 16' -glass layer;

17' -silver particles;

1-a solar cell;

11-a substrate;

12-tunneling oxide;

13-doping the conductive layer;

14-a first passivation layer;

15-a first electrode;

16-glass layer;

161-a first contact area;

162-a second contact region;

163-first conductive particles;

164-second conductive particles;

165-third conductive particles;

17-a diffusion layer;

18-a second passivation layer;

19-a second electrode.

The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the application and together with the description, serve to explain the principles of the application.

Detailed Description

For a better understanding of the technical solution of the present application, the following detailed description of the embodiments of the present application refers to the accompanying drawings.

It should be understood that the described embodiments are merely some, but not all, embodiments of the application. All other embodiments, which can be made by those skilled in the art based on the embodiments of the application without making any inventive effort, are intended to be within the scope of the application.

The terminology used in the embodiments of the application is for the purpose of describing particular embodiments only and is not intended to be limiting of the application. As used in this 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.

It should be understood that the term "and/or" as used herein is merely one relationship describing the association of the associated objects, meaning that there may be three relationships, e.g., a and/or B, may represent: a exists alone, A and B exist together, and B exists alone. In addition, the character "/" herein generally indicates that the front and rear associated objects are an "or" relationship.

It should be noted that, the terms "upper", "lower", "left", "right", and the like in the embodiments of the present application are described in terms of the angles shown in the drawings, and should not be construed as limiting the embodiments of the present application. In the context of this document, it will also be understood that when an element is referred to as being "on" or "under" another element, it can be directly on the other element or be indirectly on the other element through intervening elements.

As shown in fig. 1, a schematic diagram of a passivation contact structure of a conventional solar cell 1 '(passivation contact cell TOPCon) is shown from inside to outside, including a substrate layer 11', a tunneling layer 12', a doped polysilicon layer 13', a surface passivation layer 14', and a metal electrode 15'. The metal electrode 15 'is typically prepared by screen printing a metallic silver paste, and the metal electrode 15' forms an ohmic contact with the doped polysilicon layer 13 'through the surface passivation layer 14'.

The metal paste is coated on the surface of the surface passivation layer 14' by a screen printing mode, and glass powder contained in the metal paste reacts with the surface passivation layer 14' to form a glass layer 16' through a high-temperature sintering process. Silver particles 17' precipitated in the metal paste penetrate the glass layer 16' to contact the doped polysilicon layer 13' and form a path with the metal in the electrode body. The size of the precipitated silver particles 17' is about 10nm to 120nm, and the size of the silver particles 17' contacting the doped polysilicon layer 13' is mainly concentrated at 50nm to 120nm.

Therefore, the silver particles 17 'are generally larger in size, so that the doped polysilicon layer 13' has serious parasitic absorption, the short-circuit current of the battery is lost, and the photoelectric conversion efficiency and the power generation double-sided rate of the battery are reduced.

If the whole thickness of the polysilicon layer is simply reduced, silver particles 17' in the region of the metal electrode 15' are liable to penetrate through the doped polysilicon layer 13' and the tunneling layer 12' to directly contact with the substrate layer 11', forming a carrier recombination center, and causing the loss of open-circuit voltage of the battery.

If the size of the silver particles 17' is simply reduced, the gap distance of the silver particles 17' is increased, a passage cannot be formed between the silver particles 17', and electron transmission cannot be realized by quantum tunneling effect, so that the photo-generated current of the battery is led out and lost, and the short-circuit current and the filling factor of the battery are reduced.

For this reason, the present embodiment provides a solar cell 1 to solve the above technical problems.

Fig. 2 shows a schematic cross-sectional view of a solar cell 1, comprising a substrate 11, a tunnel oxide layer 12, a doped conductive layer 13, a first passivation layer 14, a first electrode 15, a diffusion layer 17, a second passivation layer 18 and a second electrode 19.

Wherein the substrate 11 has a first surface and a second surface. The substrate 11 may include P-type monocrystalline silicon doped with a P-type doping element (e.g., boron or gallium) or N-type monocrystalline silicon doped with a P-type doping element (e.g., phosphorus). The present embodiment is not particularly limited in the type of the substrate 11.

The diffusion layer 17 is located on the first surface, the second passivation layer 18 is located on a side of the diffusion layer 17 remote from the first surface, and the second electrode 19 is located on a side of the second passivation layer 18 remote from the diffusion layer 17.

The tunneling oxide layer 12 is disposed on the second surface, and the tunneling oxide layer 12 is mainly made of one or more of silicon oxide, silicon oxynitride, aluminum oxide, and aluminum oxynitride, and may contain impurity elements, including one or more of boron, gallium, and phosphorus impurities. The tunnel oxide layer 12 may have a thickness of 0.5nm to 2nm.

The doped conductive layer 13 is located on a side of the tunneling oxide layer 12 away from the second surface, and the main material of the doped conductive layer 13 is polysilicon, which may contain impurity elements including one or more of boron, gallium, phosphorus, and carbon elements. The thickness of the doped conductive layer 13 is 10nm to 300nm. Note that the doping type of the doped conductive layer 13 is the same as that of the substrate 11.

The first passivation layer 14 is located on a side of the doped conductive layer 13 away from the tunneling oxide layer 12, and the main material of the first passivation layer 14 is one or more of silicon nitride, silicon oxynitride, silicon oxide, aluminum oxide, and aluminum oxynitride. The thickness of the first passivation layer 14 is 50nm to 150nm.

The first electrode 15 is located at one side of the first passivation layer 14 far away from the doped conductive layer 13, the width of the electrode main body grid line is 15-80 μm, and the material of the first electrode 15 is silver or an alloy of silver and metals such as gold, aluminum, copper, nickel and the like.

Fig. 3 shows a schematic microscopic view of a passivation contact structure in a solar cell 1, comprising a substrate 11, a doped conductive layer 13, a first electrode 15 and a glass layer 16. Fig. 4 is a schematic diagram showing a passivation contact structure of the solar cell 1, which includes a substrate 11, a tunnel oxide layer 12, a doped conductive layer 13, a first electrode 15, and a glass layer 16. Referring to fig. 3 and 4 in combination, the glass layer 16 is located between the first electrode 15 and the doped conductive layer 13, the glass layer 16 is formed by reacting glass powder contained in a metal paste for forming the first electrode 15 with the first passivation layer 14 in a corresponding region of the first electrode 15, and the thickness of the glass layer 16 is 10nm to 500nm. The major components of the glass layer 16 include one or more of silicon oxide, silicon nitride, silicon oxynitride, silicate, lead oxide, aluminum oxide, boric acid, and the like.

A plurality of first contact regions 161 and a plurality of second contact regions 162 are disposed within the glass layer 16. The first contact region 161 and the second contact region 162 are provided with a plurality of conductive particles, adjacent conductive particles are not connected with each other, and the distance between the adjacent conductive particles is less than or equal to 10nm, so that the condition of quantum tunneling effect can be met between the adjacent conductive particles, and a transmission path of electrons is formed between the adjacent conductive particles, thereby realizing the transmission of electrons. And the distance between the first electrode 15 and the adjacent conductive particles is less than or equal to 10nm, and the distance between the doped conductive layer 13 and the adjacent conductive particles is less than or equal to 10nm, so that the conditions of quantum tunneling effect are met between the first electrode 15 and the adjacent conductive particles, and between the doped conductive layer 13 and the adjacent conductive particles, and electron transmission paths are formed between the first electrode 15 and the adjacent conductive particles, and between the doped conductive layer 13 and the adjacent conductive particles, thereby realizing electron transmission.

In this embodiment, by providing the first contact region 161 and the second contact region 162 with a smaller pitch, the quantum tunneling condition of electrons can be satisfied between adjacent conductive particles. In addition, the first contact region 161 and the second contact region 162 are arranged to have smaller intervals between the first electrode 15 and the adjacent conductive particles and between the doped conductive layer 13 and the adjacent conductive particles, so that electrons can be conducted between the conductive particles and the first electrode 15 through quantum tunneling effect, thereby forming a transmission path of electrons between the adjacent conductive particles, realizing the transmission of electrons, and further improving the photo-generated current export efficiency of the solar cell 1.

It should be noted that adjacent means close to each other, short in distance, closest to each other, but not in contact with each other.

In some embodiments, the contact types of the first contact region 161 and the second contact region 162 are different, specifically, the kinds of conductive particles in the first contact region 161 and the second contact region 162 are different.

The structure and preparation method of the first contact region 161 and the second contact region 162 will be specifically described below.

Fig. 5 is a schematic view of the first contact region 161, fig. 6 is a SEM actual view of the first contact region 161, and referring to fig. 5 and 6 in combination, the first contact region 161 includes two types of conductive particles. That is, the first contact region 161 includes therein a plurality of first conductive particles 163 and a plurality of second conductive particles 164. It should be noted that the doped polysilicon layer in fig. 6 refers to the doped conductive layer in fig. 5, the silver particle type i in fig. 6 refers to the first conductive particle in fig. 5, and the silver particle type ii in fig. 6 refers to the second conductive particle in fig. 5.

The first conductive particles 163 and the second conductive particles 164 are distinguished by different positions where the conductive particles in the first contact region 161 are formed in the present embodiment. With continued reference to fig. 5 and 6, the first conductive particles 163 are located at the interface between the glass layer 16 and the doped conductive layer 13, and are in contact with the doped conductive layer 13, and the second conductive particles 164 are located in the glass layer 16.

Wherein, the distance between the adjacent first conductive particles 163 and second conductive particles 164 is less than or equal to 10nm. The second conductive particles 164 are distributed in the contact regions of the glass layer 16 in the form of particle clusters, the second conductive particles 164 in the particle clusters are not connected to each other, and the interval between adjacent second conductive particles 164 is less than or equal to 10nm. The distance between the first electrode 15 and the adjacent second conductive particles 164 is less than or equal to 10nm.

Illustratively, the spacing between adjacent first conductive particles 163 and second conductive particles 164 may be 2nm, 4nm, 6nm, 8nm, 10nm, etc., the spacing between adjacent second conductive particles 164 within a particle cluster may be 2nm, 4nm, 6nm, 8nm, 10nm, etc., and the spacing between the first electrode 15 and adjacent second conductive particles 164 may be 2nm, 4nm, 6nm, 8nm, 10nm, etc.

In this embodiment, the distance between the adjacent first conductive particles 163 and second conductive particles 164 should not be larger than 10nm, and if the distance is too large, a path cannot be formed between the first conductive particles 163 and the second conductive particles 164, so that the quantum tunneling condition of electrons cannot be satisfied between the first conductive particles 163 and the second conductive particles 164, and electron transmission cannot be realized, resulting in loss of photo-generated current derivation of the battery.

Similarly, the distance between the adjacent second conductive particles 164 in the particle cluster should not be greater than 10nm, if the distance is too large, a path cannot be formed between the adjacent second conductive particles 164, then the quantum tunneling condition of electrons cannot be satisfied between the adjacent second conductive particles 164, and the transmission of electrons cannot be realized, so that the photo-generated current of the battery is lost.

The distance between the first electrode 15 and the adjacent second conductive particles 164 should not be greater than 10nm, if the distance is too large, a path cannot be formed between the first electrode 15 and the adjacent second conductive particles 164, so that the quantum tunneling condition of electrons cannot be satisfied between the first electrode 15 and the adjacent second conductive particles 164, the transmission of electrons cannot be realized, and the photo-generated current of the battery is lost.

Therefore, in the present embodiment, by setting the distance between the adjacent first conductive particles 163 and the second conductive particles 164 in the first contact region 161 to be smaller, the distance between the adjacent second conductive particles 164 to be smaller, and the distance between the first electrode 15 and the adjacent second conductive particles 164 to be smaller, electrons can be conducted through quantum tunneling effect, so as to realize the transmission of electrons, and improve the efficiency of exporting the photo-generated current of the solar cell 1.

The second conductive particles 164 are formed in the glass layer 16 in the form of particle clusters, and may be divided into contact regions according to regions where the clusters are located.

Further, in the first contact region 161, the size of the first conductive particles 163 is equal to or less than 20nm, and the size of the second conductive particles 164 is equal to or less than 10nm.

Illustratively, the first conductive particles 163 may have a size of 4nm, 8nm, 12nm, 16nm, 20nm, or the like. The second conductive particles 164 may have a size of 2nm, 4nm, 6nm, 8nm, 10nm, etc.

In this embodiment, the size of the first conductive particles 163 should not be larger than 20nm, if the size is too large, the etching damage to the doped conductive layer 13 increases, and when the doped conductive layer 13 is thinned, the first conductive particles 163 easily penetrate the tunnel oxide layer 12 to contact with the substrate 11 to form a carrier recombination center, resulting in loss of the open-circuit voltage of the solar cell 1.

Similarly, in this embodiment, the size of the second conductive particles 164 should not be greater than 10nm, if the size is too large, the etching damage to the doped conductive layer 13 increases, and when the doped conductive layer 13 is thinned, the second conductive particles 164 easily penetrate through the tunnel oxide layer 12 to contact with the substrate 11 to form a carrier recombination center, resulting in a loss of the open-circuit voltage of the solar cell 1.

Therefore, in the present embodiment, by forming the first conductive particles 163 and the second conductive particles 164 with smaller sizes in the first contact region 161, etching damage to the doped conductive layer 13 is reduced, and loss of the open-circuit voltage of the solar cell 1 caused by the fact that the first conductive particles 163 penetrate through the tunnel oxide layer 12 to contact with the substrate 11 to form carrier recombination centers is avoided. Meanwhile, the thinning of the doped conductive layer 13 can be realized, the optical parasitic absorption is reduced, and the photoelectric conversion rate of the solar cell 1 is improved.

In this embodiment, while the sizes of the first conductive particles 163 and the second conductive particles 164 are reduced, the distances between the adjacent first conductive particles 163 and the second conductive particles 164, between the adjacent second conductive particles 164 in the particle cluster, and between the first electrode 15 and the adjacent second conductive particles 164 are correspondingly reduced, so that the etching damage to the doped conductive layer 13 is reduced, the thinning of the doped conductive layer 13 is realized, and the transmission of current is satisfied.

Fig. 7 is a schematic view of the second contact region 162, fig. 8 is a SEM actual view of the second contact region 162, and referring to fig. 7 and 8 in combination, the second contact region 162 includes three types of conductive particles. That is, the second contact region 162 includes a plurality of first conductive particles 163, a plurality of second conductive particles 164, and third conductive particles 165. Note that the doped polysilicon layer in fig. 8 refers to the doped conductive layer in fig. 7, the silver particle type i in fig. 8 refers to the first conductive particle in fig. 7, the silver particle type ii in fig. 8 refers to the second conductive particle in fig. 7, and the silver particle type iii in fig. 8 refers to the third conductive particle in fig. 7.

In this embodiment, the first conductive particles 163 and the second conductive particles 164 are separated by different positions of the conductive particles in the first contact region 161, and the second conductive particles 164 and the third conductive particles 165 are separated by different shapes and sizes of the conductive particles. With continued reference to fig. 7 and 8, the first conductive particles 163 are located at the interface between the glass layer 16 and the doped conductive layer 13, and are in contact with the doped conductive layer 13, and the second conductive particles 164 are located in the glass layer 16. The third conductive particles 165 are in a crotch shape and are positioned on the glass layer 16, the size of the third conductive particles 165 is larger than that of the second conductive particles 164, and the plurality of second conductive particles 164 are distributed around the third conductive particles 165.

Wherein, the distance between the adjacent first conductive particles 163 and second conductive particles 164 is less than or equal to 10nm. Illustratively, the spacing between adjacent first and second conductive particles 163, 164 may be 2nm, 4nm, 6nm, 8nm, 10nm, etc.

The second conductive particles 164 are distributed in the contact regions of the glass layer 16 in the form of particle clusters, the second conductive particles 164 in the particle clusters are not connected to each other, and the interval between adjacent second conductive particles 164 is less than or equal to 10nm. Illustratively, the spacing between adjacent second conductive particles 164 within a particle cluster may be 2nm, 4nm, 6nm, 8nm, 10nm, etc.

In this embodiment, the distance between the adjacent second conductive particles 164 in the particle cluster should not be greater than 10nm, and if the distance is too large, a path cannot be formed between the adjacent second conductive particles 164, so that the quantum tunneling condition of electrons cannot be satisfied between the adjacent second conductive particles 164, and the transmission of electrons cannot be realized, resulting in the loss of photo-generated current derivation of the battery.

The distance between the first electrode 15 and the adjacent second conductive particles 164 is less than or equal to 10nm. Illustratively, the spacing between the first motor and the adjacent second conductive particles 164 may be 2nm, 4nm, 6nm, 8nm, 10nm, etc.

In this embodiment, the distance between the first electrode 15 and the adjacent second conductive particle 164 should not be larger than 10nm, and if the distance is too large, a path cannot be formed between the first electrode 15 and the adjacent second conductive particle 164, so that the quantum tunneling condition of electrons cannot be satisfied between the first electrode 15 and the adjacent second conductive particle 164, and electron transmission cannot be realized, resulting in loss of photo-generated current derivation of the battery.

The second conductive particles 164 are formed in the glass layer 16 in the form of particle clusters, and may be divided into contact regions according to regions where the clusters are located. And, the above distribution of the plurality of second conductive particles 164 around the third conductive particles 165 means that the third conductive particles 165 are located within a particle cluster composed of the plurality of second conductive particles 164, and the plurality of second conductive particles 164 are disposed around the third conductive particles 165.

The third conductive particles 165 have first and second ends disposed in opposite directions along the thickness direction Z of the solar cell 1. The first end may be the end of the third conductive particle 165 closest to the doped conductive layer 13, and the second end may be the end of the third conductive particle 165 closest to the first electrode 15.

As shown in fig. 7, 9-11, which are schematic views of the second contact region 162, there may be various situations for specific positions of the first and second ends of the third conductive particles 165.

As shown in fig. 9, in one case, the first end is located in the glass layer 16 and extends toward the doped conductive layer 13, the first end is spaced from the adjacent first conductive particles 163 by 10nm or less, and the second end is in contact with the first electrode 15.

Illustratively, the spacing between the first end and the adjacent first conductive particles 163 may be 2nm, 4nm, 8nm, 10nm, etc.

In this embodiment, the distance between the first end and the adjacent first conductive particle 163 should not be greater than 10nm, and if the distance is too large, the first end and the adjacent first conductive particle 163 cannot form a path, so that the quantum tunneling condition of electrons cannot be satisfied, and the electron transmission cannot be realized.

In this embodiment, the first end of the third conductive particle 165 is arranged at a smaller distance from the first conductive particle 163, so that electrons can be conducted by quantum tunneling effect, and the second end is arranged in contact with the first electrode 15, so that electrons are directly conducted to the first electrode 15 along the third conductive particle 165. In this embodiment, the second contact region 162 is provided with the first conductive particles 163 and the second conductive particles 164 to realize electron conduction through quantum tunneling effect, and the third conductive particles 165 are further provided in the second contact region 162 to realize electron conduction, so that a conductive path is increased, further, the open-circuit voltage, the short-circuit current and the filling factor of the solar cell 1 are improved, and the efficiency of guiding out the effective photo-generated current is improved.

As shown in fig. 10, in one case, the first end is located at the interface of the glass layer 16 and the doped conductive layer 13. The second end is positioned in the glass layer 16 and extends towards the first electrode 15, and the distance between the second end and the first electrode 15 is less than or equal to 10nm.

Illustratively, the spacing between the second end and the first electrode 15 may be 2nm, 4nm, 8nm, 10nm, etc.

In this embodiment, the distance between the second end and the first electrode 15 should not be greater than 10nm, and if the distance is too large, a path cannot be formed between the second end and the adjacent first electrode 15 because the second end is not in contact with the first electrode 15, and the quantum tunneling condition of electrons cannot be satisfied between the second end and the first electrode 15, so that electron transmission cannot be realized.

In this embodiment, the first end of the third conductive particle 165 is in contact with the doped conductive layer 13, so that electrons can be directly conducted along the third conductive particle 165, and the distance between the second end and the first electrode 15 is smaller, so that electrons are conducted to the first electrode 15 through quantum tunneling effect. In this embodiment, the second contact region 162 is provided with the first conductive particles 163 and the second conductive particles 164 to realize electron conduction through quantum tunneling effect, and the third conductive particles 165 are further provided in the second contact region 162 to realize electron conduction, so that a conductive path is increased, further, the open-circuit voltage, the short-circuit current and the filling factor of the solar cell 1 are improved, and the efficiency of guiding out the effective photo-generated current is improved.

As shown in fig. 7, in one case, the first end is located at the interface of the glass layer 16 and the doped conductive layer 13. The second end is in contact with the first electrode 15.

In this embodiment, the first end of the third conductive particle 165 is disposed in contact with the doped conductive layer 13, and the second end is disposed in contact with the first electrode 15, so that electrons can be conducted to the first electrode 15 through direct contact. In this embodiment, the second contact region 162 is provided with the first conductive particles 163 and the second conductive particles 164 to realize electron conduction through quantum tunneling effect, and the third conductive particles 165 are further provided in the second contact region 162 to realize electron conduction, so that a conductive path is increased, further, the open-circuit voltage, the short-circuit current and the filling factor of the solar cell 1 are improved, and the efficiency of guiding out the effective photo-generated current is improved.

In one case, as shown in FIG. 11, the first end is located within the glass layer 16 and extends in the direction of the doped conductive layer 13, with a spacing of 10nm or less between the first end and the adjacent first conductive particles 163. The second end is positioned in the glass layer 16 and extends towards the first electrode 15, and the distance between the second end and the first electrode 15 is less than or equal to 10nm.

Illustratively, the spacing between the first end and the adjacent first conductive particles 163 may be 2nm, 4nm, 8nm, 10nm, etc. The spacing between the second end and the first electrode 15 may be 2nm, 4nm, 8nm, 10nm, etc.

Similarly, in the present embodiment, the distance between the second end and the first electrode 15 should not be greater than 10nm, and if the distance is too large, a path cannot be formed between the second end and the adjacent first electrode 15 because the second end is not in contact with the first electrode 15, and the quantum tunneling condition of electrons cannot be satisfied between the second end and the first electrode 15, so that electron transmission cannot be realized.

In this embodiment, by setting the space between the first end of the third conductive particle 165 and the first conductive particle 163 smaller, the space between the second end and the first electrode 15 is set smaller, so that electrons can be conducted to the first electrode 15 by quantum tunneling effect. In this embodiment, the second contact region 162 is provided with the first conductive particles 163 and the second conductive particles 164 to realize electron conduction through quantum tunneling effect, and the third conductive particles 165 are further provided in the second contact region 162 to realize electron conduction, so that a conductive path is increased, further, the open-circuit voltage, the short-circuit current and the filling factor of the solar cell 1 are improved, and the efficiency of guiding out the effective photo-generated current is improved.

Further, in the second contact region 162, the size of the first conductive particles 163 is 20nm or less, the size of the second conductive particles 164 is 10nm or less, and the size of the third conductive particles 165 is 20nm to 150nm.

Illustratively, the first conductive particles 163 may have a size of 4nm, 8nm, 12nm, 16nm, 20nm, or the like. The second conductive particles 164 may have a size of 2nm, 4nm, 6nm, 8nm, 10nm, etc. The size of the third conductive particles 165 may be 20nm, 40nm, 60nm, 80nm, 100nm, 120nm, 140nm, etc.

In this embodiment, the size of the third conductive particles 165 should not be too large or too small, and if the size is too large (e.g. greater than 150 nm), the third conductive particles 165 may penetrate the tunnel oxide layer 12 to contact the substrate 11 to form a carrier recombination center, resulting in a loss of the open-circuit voltage of the solar cell 1; if the size is too small (e.g. less than 20 nm), the spacing between the third conductive particles 165 and the adjacent first conductive particles 163, the adjacent second conductive particles 164 and the first electrode 15 is too large, a path cannot be formed, the quantum tunneling condition of electrons cannot be satisfied, the transmission of electrons cannot be realized, and the photo-generated current of the battery is lost.

Therefore, in the present embodiment, by forming the first conductive particles 163 and the second conductive particles 164 with smaller dimensions in the second contact region 162, etching damage to the doped conductive layer 13 is reduced, and loss of the open-circuit voltage of the solar cell 1 caused by the fact that the first conductive particles 163 penetrate through the tunnel oxide layer 12 to contact with the substrate 11 to form carrier recombination centers is avoided. Meanwhile, the thinning of the doped conductive layer 13 can be realized, the optical parasitic absorption is reduced, and the photoelectric conversion rate of the solar cell 1 is improved.

In addition, the second contact region 162 is further provided with a third conductive particle 165, and the third conductive particle 165 can form quantum tunneling effect with the first conductive particle 163 and the first electrode 15 to realize electron conduction, and the third conductive particle 165 can be connected with the doped conductive layer 13 and the first electrode 15 in a contact manner to realize direct electron conduction, so that a conductive path is increased.

In some embodiments, glass layer 16 may have one or both of first contact region 161 and second contact region 162 therein.

In the schematic diagram of the passivation contact structure shown in fig. 4, the passivation contact structure includes a substrate 11, a tunneling oxide layer 12, a doped conductive layer 13, a first passivation layer 14, a glass layer 16, and a first electrode 15. Wherein the glass layer 16 comprises a first contact region 161 and a second contact region 162.

In the schematic diagram of the passivation contact structure shown in fig. 12, the passivation contact structure includes a substrate 11, a tunneling oxide layer 12, a doped conductive layer 13, a first passivation layer 14, a glass layer 16, and a first electrode 15. Wherein only the first contact region 161 is included in the glass layer 16.

In the schematic diagram of the passivation contact structure shown in fig. 12, the passivation contact structure includes a substrate 11, a tunneling oxide layer 12, a doped conductive layer 13, a first passivation layer 14, a glass layer 16, and a first electrode 15. Wherein only the second contact region 162 is included in the glass layer 16.

In the embodiment shown in fig. 4,12 and 13, the third conductive particles 165 in the second contact region 162 may be any one of the third conductive particles 165 in fig. 7, 9 to 11.

In order to realize the passivation contact structure, the embodiment also provides a preparation method of the solar cell 1. As shown in fig. 14, a process flow diagram for preparing a passivation contact structure is shown, the method comprising: forming a tunnel oxide layer 12 on a second surface of the substrate 11; forming a doped conductive layer 13 on the surface of the tunneling oxide layer 12 far from the substrate 11, and cleaning the doped conductive layer 13; forming a first passivation layer 14 on the surface of the doped conductive layer 13 away from the tunneling oxide layer 12; screen printing a metal paste on the surface of the first passivation layer 14 remote from the doped conductive layer 13; performing a high-temperature sintering process on the metal paste to enable glass powder contained in the metal paste to react with the corresponding first passivation layer 14 to form a first electrode 15, a glass layer 16 positioned between the first electrode 15 and the doped conductive layer 13 and a plurality of first contact areas 161 positioned in the glass layer 16, wherein the first contact areas 161 are internally provided with a plurality of conductive particles; the first contact region 161 is subjected to a laser process, and a portion of the conductive particles can be crosslinked, so that a portion of the first contact region 161 is converted into a second contact region 162.

In this embodiment, a portion of the conductive particles in the portion of the first contact region 161 is crosslinked by a laser process, so that a portion of the first contact region 161 is converted into the second contact region 162, so that the types of the conductive particles in the first contact region 161 are different from those in the second contact region 162, thereby increasing the types of the conductive particles and further facilitating the increase of the conductive channels.

Wherein the plurality of first conductive particles 163 and the plurality of second conductive particles 164 are formed through a high temperature sintering process. The first plurality of conductive particles 163 are located at the interface of the glass layer 16 and the doped conductive layer 13 and are in contact with the doped conductive layer 13, and the second plurality of conductive particles 164 are located within the glass layer 16.

Mainly, the temperature employed in the high-temperature sintering process of the present embodiment is 650 to 800 ℃, so that the first conductive particles 163 and the second conductive particles 164 having smaller sizes are formed, and the pitches between the adjacent first conductive particles 163 and the second conductive particles 164, between the adjacent second conductive particles 164 in the adjacent particle clusters, and between the first electrode 15 and the adjacent second conductive particles 164 are made smaller.

The size of the first conductive particles 163, the size of the second conductive particles 164, the spacing between the adjacent first conductive particles 163 and the second conductive particles 164, the spacing between the adjacent second conductive particles 164 in the particle cluster, and the size and the technical effect of the spacing between the first electrode 15 and the adjacent second conductive particles 164 are described above, and the present embodiment is not repeated here.

In some embodiments, the second contact region 162 may be formed by a laser process: in a portion of the first contact region 161, a portion of the second conductive particles 164 melt with the surrounding glass body, causing the second conductive particles 164 to crosslink and transform into third conductive particles 165 to form a second contact region 162 having the first conductive particles 163, the second conductive particles 164, and the third conductive particles 165.

The dimensions of the third conductive particles 165, the spacing between the third conductive particles 165 and the adjacent first conductive particles 163, the spacing between the third conductive particles 165 and the adjacent second conductive particles 164, and the size and technical effects of the spacing between the third conductive particles 165 and the first electrode 15 are described above, and the present embodiment is not repeated here.

In this embodiment, a part of the second conductive particles 164 is melted with the surrounding glass body, so that the second conductive particles 164 are crosslinked and converted into the third conductive particles 165, and the formed second contact region 162 may be the second contact region 162 where the third conductive particles 165 are not in contact with the doped conductive layer 13 as shown in fig. 9 and 11.

In some embodiments, the second contact region 162 may be formed by a laser process: in part of the first contact region 161, part of the second conductive particles 164 and part of the first conductive particles 163 are melted with the surrounding glass body, so that the second conductive particles 164 and the first conductive particles 163 are crosslinked and converted into third conductive particles 165, to form a second contact region 162 having the first conductive particles 163, the second conductive particles 164 and the third conductive particles 165.

In this embodiment, a part of the first conductive particles 163 and a part of the second conductive particles 164 are melted with the surrounding glass body, so that the first conductive particles 163 and the second conductive particles 164 are crosslinked and converted into the third conductive particles 165, and the formed second contact region 162 may be the second contact region 162 where the third conductive particles 165 are in contact connection with the doped conductive layer 13 as shown in fig. 7 and 10.

In some embodiments, the diffusion layer 17 is formed on the first surface of the substrate 11, the second passivation layer 18 is formed on the surface of the diffusion layer 17, and the second electrode 19 is screen-printed on the surface of the second passivation layer 18. Before performing the laser process, the method further comprises: a reverse bias voltage is externally connected between the first electrode 15 and the second electrode 19, an electric field directed from the first electrode 15 to the second electrode 19 is formed, and the surface of the first electrode 15 or the surface of the second electrode 19 is locally irradiated with laser light.

Further, the external reverse bias voltage between the first electrode 15 and the second electrode 19 is 10V-20V, so that the direction of the internal electric field of the solar cell 1 is directed from the first electrode 15 to the second electrode 19. The incident light source defining the laser process is a monochromatic laser or a mixed laser having a wavelength of 632nm to 1550nm, the spot size of the laser process is 0.005mm ²～0.01mm², the speed of the laser process is 50000mm/s to 60000mm/s, so that the photo-generated current density generated by irradiation of the laser process is 20000A/cm ²～45000A/cm², thereby realizing that the thermal effect generated by the local photo-generated current melts a part of the glass body around the second conductive particles 164, or melts a part of the second conductive particles 164 and a part of the first conductive particles 163 with the surrounding glass body, so that a part of the second conductive particles 164 are crosslinked to be converted into the third conductive particles 165, or crosslinks a part of the second conductive particles 164 and a part of the first conductive particles 163 to be converted into the third conductive particles 165, thereby realizing that a part of the first contact region 161 is converted into the second contact region 162.

Specifically, the incident light source of the laser process may be an infrared continuous laser with a wavelength of 1080 nm. The laser light may perform a scanning process on the surface of the second electrode 19.

By adopting the method for preparing the passivation contact structure in the embodiment, the size of the conductive particles precipitated by the metal slurry is smaller than that of a conventional battery, and the etching damage to the doped conductive layer 13 is smaller, so that higher battery open-circuit voltage can be obtained, and the battery structure of the doped conductive layer 13 with the thickness smaller than 30nm can be adapted. The distance between the conductive particles can be reduced while the conductive particles are reduced, so that the quantum tunneling effect condition of electrons is met, and the transmission of electrons is realized. In addition, the mutually separated conductive particles are connected by adopting laser treatment, so that a conductive path is further increased, and the short-circuit current and the filling factor of the solar cell 1 are higher.

The embodiment also provides a photovoltaic module, which comprises a first cover plate, a first adhesive film, a battery string, a second adhesive film and a second cover plate which are arranged in a stacked mode, wherein the battery string comprises a plurality of solar cells 1 which are electrically connected.

The first cover plate is positioned on the light-oriented side of the battery string and used for transmitting sunlight and improving the waterproof and moistureproof capacity of the photovoltaic module, and the first cover plate and the second cover plate seal the battery string together. In the lamination process of the photovoltaic module, the first adhesive film and the second adhesive film are used for packaging and protecting the battery string, so that the influence of the external environment on the performance of the battery string is prevented, and the first cover plate, the battery string and the second cover plate can be bonded into a whole.

The material of the first adhesive film and the second adhesive film can be one of Ethylene-vinyl acetate Copolymer (Ethylene-VINYL ACETATE Copolymer EVA), polyolefin elastomer (Polyolefin Elastomer POE), polyvinyl butyral (Polyvinyl Butyral PVB) and other materials, and can also be an EPE adhesive film (EVA-POE-EVA co-extrusion structure) or an EP adhesive film (EVA-EP co-extrusion structure).

The embodiment also provides a laminated battery, which comprises a top battery, an intermediate connecting layer and a bottom battery, wherein the intermediate connecting layer is connected between the bottom battery and the top battery. The top cell is one of perovskite cell, cadmium telluride solar cell, copper indium gallium selenium solar cell or gallium arsenide solar cell, and the bottom cell is the solar cell 1. The choice of intermediate tie layer is typically selected from transparent materials with high refractive index. Efficient intermediate connection layers are required to have high optical transmission to reduce reflection and absorption of light at the interface of the connection layers, and good electrical conductivity to reduce the impact of series resistance on device performance. Illustratively, a transparent conductive metal oxide film (ITO) may be used as the intermediate connection layer.

The above description is only of the preferred embodiments of the present application and is not intended to limit the present application, but various modifications and variations can be made to the present application by those skilled in the art. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application should be included in the protection scope of the present application.

Claims

1. A solar cell, characterized in that the solar cell (1) comprises:

A substrate (11);

A doped conductive layer (13) located on one side of the substrate (11);

a first electrode (15) located on a side of the doped conductive layer (13) remote from the substrate (11), the first electrode (15) being electrically connected to the doped conductive layer (13);

-a glass layer (16), the glass layer (16) being located between the first electrode (15) and the doped conductive layer (13);

-a plurality of first contact areas (161) and/or a plurality of second contact areas (162) are provided within the glass layer (16);

the first contact area (161) and the second contact area (162) are internally provided with a plurality of conductive particles, the adjacent conductive particles are not connected with each other, and the distance between the adjacent conductive particles is less than or equal to 10nm;

The conductive particles in the first contact region (161) are of a different type than the conductive particles in the second contact region (162).

2. Solar cell according to claim 1, characterized in that the spacing between the first electrode (15) and adjacent conductive particles is 10nm or less, and the spacing between the doped conductive layer (13) and adjacent conductive particles is 10nm or less.

3. The solar cell of claim 2, wherein the conductive particles comprise first conductive particles, second conductive particles, and third conductive particles.

4. A solar cell according to claim 3, characterized in that a plurality of the first conductive particles (163) and a plurality of the second conductive particles (164) are provided within the first contact region (161);

-a plurality of said first conductive particles (163) are located at the interface of said glass layer (16) and said doped conductive layer (13) and are in contact with said doped conductive layer (13);

A plurality of second conductive particles (164) are positioned in the glass layer (16), and the distance between the first electrode (15) and the adjacent second conductive particles (164) is less than or equal to 10nm.

5. A solar cell according to claim 3, characterized in that a plurality of the first conductive particles (163), a plurality of the second conductive particles (164) and a third conductive particle (165) are provided within the second contact region (162);

A plurality of second conductive particles (164) are positioned in the glass layer (16), and the distance between the first electrode (15) and the adjacent second conductive particles (164) is less than or equal to 10nm;

the third conductive particles (165) are in a crotch shape, and a plurality of the second conductive particles (164) are distributed around the third conductive particles (165).

6. The solar cell according to claim 5, wherein the third conductive particles (165) have opposite first and second ends in the thickness direction of the solar cell (1);

The first end is positioned in the glass layer (16) and extends towards the doped conductive layer (13), and the distance between the first end and the adjacent first conductive particles (163) is less than or equal to 10nm;

The second end is in contact with the first electrode (15).

7. The solar cell according to claim 5, characterized in that the third conductive particles (165) have opposite first and second ends in the thickness direction (Z) of the solar cell (1);

the first end is located at an interface of the glass layer (16) and the doped conductive layer (13);

The second end is positioned in the glass layer (16) and extends towards the first electrode (15), and the distance between the second end and the first electrode (15) is less than or equal to 10nm.

8. The solar cell according to claim 5, characterized in that the third conductive particles (165) have opposite first and second ends in the thickness direction (Z) of the solar cell (1);

the first end is located at the interface of the glass layer (16) and the doped conductive layer (13), and the second end is in contact with the first electrode (15).

9. The solar cell according to claim 5, characterized in that the third conductive particles (165) have opposite first and second ends in the thickness direction (Z) of the solar cell (1);

10. A solar cell according to claim 3, wherein the first conductive particles (163) have a size of 20nm or less.

11. A solar cell according to claim 3, characterized in that the second conductive particles (164) have a size of 10nm or less.

12. A solar cell according to claim 3, characterized in that the third conductive particles (165) have a size of 20nm to 150nm.

13. A method of manufacturing a solar cell, the method comprising:

Forming a doped conductive layer (13) on the surface of a substrate (11);

forming a first passivation layer (14) on the surface of the doped conductive layer (13);

printing a metal paste on the surface of the first passivation layer (14) far away from the doped conductive layer (13);

Performing a sintering process on the metal paste to form a first electrode (15), a glass layer (16) positioned between the first electrode (15) and the doped conductive layer (13), and a plurality of first contact areas (161) positioned in the glass layer (16), wherein the first contact areas (161) are internally provided with a plurality of conductive particles;

-subjecting said first contact region (161) to a laser process, a portion of said conductive particles being capable of cross-linking, transforming a portion of said first contact region (161) into a second contact region (162).

14. The method of manufacturing a solar cell according to claim 13, wherein a plurality of first conductive particles (163) and a plurality of second conductive particles (164) are disposed within the first contact region (161) formed through the sintering process;

a plurality of the second conductive particles (164) are located within the glass layer (16).

15. The method of claim 13, further comprising:

The temperature of the sintering process is 650-800 ℃.

16. The method of manufacturing a solar cell according to claim 14, wherein the method of forming the second contact region (162) under the influence of the laser process comprises:

In a portion of the first contact region (161), a portion of the second conductive particles (164) melts with surrounding glass bodies, causing the second conductive particles (164) to crosslink into third conductive particles (165) to form the second contact region (162) with the first conductive particles (163), the second conductive particles (164), and the third conductive particles (165).

17. The method of manufacturing a solar cell according to claim 14, wherein the method of forming the second contact region (162) under the influence of the laser process comprises:

Part of the first contact region (161), part of the second conductive particles (164) and part of the first conductive particles (163) are melted with surrounding glass bodies, so that the second conductive particles (164) and the first conductive particles (163) are crosslinked and converted into third conductive particles (165) to form the second contact region (162) with the first conductive particles (163), the second conductive particles (164) and the third conductive particles (165).

18. A method of manufacturing a solar cell according to claim 13, characterized in that the second surface of the substrate (11) is provided with a second electrode (19), the method further comprising, prior to performing the laser process:

A reverse bias voltage is externally connected between the first electrode (15) and the second electrode (19), so that an electric field directed to the second electrode (19) by the first electrode (15) is formed.

19. The method of claim 18, wherein the solar cell is fabricated by a method comprising,

The external reverse bias voltage between the first electrode (15) and the second electrode (19) is 10V-20V;

the spot size of the laser process is 0.005mm ²～0.01mm²;

the speed of the laser process is 50000 mm/s-60000 mm/s;

20. The photovoltaic module is characterized by comprising a first cover plate, a first adhesive film, a battery string, a second adhesive film and a second cover plate which are arranged in a stacked manner;

The cell string comprises a plurality of electrically connected solar cells (1), the solar cells (1) being the solar cells (1) of any one of claims 1 to 12.

21. A laminated battery, characterized in that the laminated battery comprises:

bottom cell, which is a solar cell (1) according to any one of claims 1 to 12;