Photovoltaic cell and manufacturing method thereof, laminated cell, and photovoltaic module

Abstract

The embodiments of the present disclosure relate to the photovoltaic field and provide a photovoltaic cell and a manufacturing method thereof, a laminated cell, and a photovoltaic module. The photovoltaic cell includes: a cell substrate having first and second opposite surfaces; a plurality of grid lines located on the first surface and / or the second surface and arranged at intervals along a first direction, the grid line including a contact structure and a connection layer electrically connected to the cell substrate, the contact structure including a plurality of contact portions, and the connection layer being a long strip structure extending along a second direction; the contact portion including first and second contact portions alternately arranged along the second direction, the connection layer having first and second side portions opposite to each other along the first direction, the first contact portion being in contact and connected with at least the first side portion and the second contact portion being in contact and connected with the second side portion, or the second contact portion being in contact and connected with at least the second side portion and the first contact portion being in contact and connected with the first side portion, which is at least beneficial to improving the electrical connection performance between the grid line and the cell substrate and reducing the manufacturing cost of the grid line.

Description

Technical Field

[0001] The present disclosure relates to the photovoltaic field, and in particular to a photovoltaic cell and a manufacturing method thereof, a laminated cell, and a photovoltaic module. Background Art

[0002] With the gradual depletion of fossil fuels, photovoltaic cells are becoming increasingly popular as a new energy alternative. Photovoltaic cells convert sunlight into electricity. They utilize the principle of photovoltaics to generate charge carriers, which are then extracted using grid lines, facilitating the efficient use of the electricity. Current photovoltaic cell types include BC cells (Back Contact), TOPCON (Tunnel Oxide Passivated Contact), PERC cells (Passivated Emitter and Real Cell), and heterojunction cells. Summary of the Invention

[0003] The embodiments of the present disclosure provide a photovoltaic cell and a manufacturing method thereof, a laminated cell, and a photovoltaic module, which are at least beneficial to improving the electrical connection performance between the grid line and the cell substrate and reducing the manufacturing cost of the grid line.

[0004] According to some embodiments of the present disclosure, on one hand, an embodiment of the present disclosure provides a photovoltaic cell, comprising: a cell substrate having a first surface and a second surface opposite to each other along a thickness direction; a plurality of grid lines located on the first surface and / or the second surface and arranged at intervals along the first direction, the grid lines comprising a contact structure electrically connected to the cell substrate and a connecting layer, the contact structure comprising a plurality of contact portions arranged in sequence along a second direction, the connecting layer being a long strip structure extending along the second direction, and the first direction and the second direction intersecting; wherein the connecting layer is in contact with and connected to the plurality of contact portions in the contact structure, the material of the contact portion is different from the material of the connecting layer, and the orthographic projections of the contact portion and the connecting layer on the cell substrate partially overlap; the contact portion comprises a first contact portion and a second contact portion arranged alternately along the second direction, the connecting layer having a first side portion and a second side portion opposite to each other along the first direction, the first contact portion being in contact with and connected to at least the first side portion and the second contact portion being in contact with and connected to the second side portion, or the second contact portion being in contact with at least the second side portion and the first contact portion being in contact with and connected to the first side portion.

[0005] In some embodiments, in the same gate line, the first contact portion and the second contact portion are not directly opposite to each other along the second direction.

[0006] In some embodiments, in the same gate line, a partial area of ​​the first contact portion and a partial area of ​​the second contact portion are opposite to each other along the second direction.

[0007] In some embodiments, along the second direction, a portion of the first contact portion facing the second contact portion is a first portion, and a width of a portion of the first contact portion other than the first portion in the first direction is less than or equal to 25 μm.

[0008] In some embodiments, along the thickness direction, the orthographic projection shape of the contact portion on the battery substrate is a circle, an ellipse, a triangle, a rectangle, a trapezoid or an N-gon, where N is a positive integer greater than 4.

[0009] In some embodiments, along the thickness direction, the orthographic projection shape of the contact portion on the battery substrate is circular or elliptical, and the first contact portion and the second contact portion adjacent to each other along the second direction are tangent to each other.

[0010] In some embodiments, along the thickness direction, the orthographic projection area of ​​the contact portion on the battery substrate is 100 μm 2 ~5000μm 2 .

[0011] In some embodiments, along the first direction, the width of the connection layer is 10 μm to 70 μm.

[0012] In some embodiments, in the first contact portion and the second contact portion adjacent to each other along the second direction, the edge of the first contact portion closest to the second contact portion is a first edge, the edge of the second contact portion closest to the first contact portion is a second edge, and the distance between the first edge and the second edge is less than or equal to 200 μm.

[0013] In some embodiments, along the thickness direction, the thickness of the contact portion is 1 μm to 10 μm; and / or the thickness of the connection layer is 4 μm to 20 μm.

[0014] In some embodiments, the gate line is one of a fine gate and a main gate, and the other of the fine gate and the main gate is a long strip structure extending along the first direction.

[0015] In some embodiments, the grid line is a fine grid, and the photovoltaic cell further includes: a plurality of main grids located on at least one of the first surface and the second surface and arranged at intervals along the second direction, the main grid including a connection structure electrically connected to the cell substrate and an interconnection layer, the connection structure including a plurality of connection parts arranged in sequence along the first direction, and the interconnection layer is a long strip structure extending along the first direction; wherein, the interconnection layer is in contact with and connected to the plurality of connection parts in the connection structure, the connection parts including a first connection part and a second connection part arranged alternately along the second direction, the interconnection layer has a third side and a fourth side opposite to each other along the first direction, the first connection part is in contact with and connected to at least the third side, the second connection part is in contact with and connected to at least the fourth side, and the material of the connection part is different from the material of the interconnection layer.

[0016] In some embodiments, the material of the contact portion includes silver particles, and the material of the connection layer includes copper particles or silver-coated copper particles.

[0017] In some embodiments, the diameter of the copper particles is 50 nm to 1500 nm; or, the diameter of the silver-coated copper particles is 1 μm to 10 μm; or, the proportion of silver in the silver-coated copper particles is 15% to 50%.

[0018] According to some embodiments of the present disclosure, another aspect of the embodiments of the present disclosure further provides a method for manufacturing a photovoltaic cell, comprising: providing a cell substrate, the cell substrate having a first surface and a second surface opposite to each other along a thickness direction; forming a plurality of grid lines arranged at intervals along a first direction on the first surface and / or the second surface, the grid lines comprising a contact structure electrically connected to the cell substrate and a connecting layer, the contact structure comprising a plurality of contact portions arranged in sequence along a second direction, the connecting layer being a long strip structure extending along the second direction, and the first direction and the second direction intersecting; wherein the connecting layer is in contact with and connected to the plurality of contact portions in the contact structure, the material of the contact portion is different from the material of the connecting layer, and the orthographic projections of the contact portion and the connecting layer on the cell substrate partially overlap; the contact portion comprises a first contact portion and a second contact portion arranged alternately along the second direction, the connecting layer having a first side portion and a second side portion opposite to each other along the first direction, the first contact portion being in contact with and connected to at least the first side portion and the second contact portion being in contact with and connected to the second side portion, or the second contact portion being in contact with at least the second side portion and the first contact portion being in contact with and connected to the first side portion.

[0019] In some embodiments, the gate line is a fine gate; the second surface has a first printing area, and a second printing area that at least partially overlaps with the first printing area; the steps of forming the gate line include: using a first screen printing process to print a first paste on the first printing area; sintering the first paste to form the contact structure corresponding to the first printing area; using a second screen printing process to print a second paste on the second surface; curing the second paste to form the connection layer corresponding to the second printing area; wherein the first paste is a burn-through type paste, and the second paste is a non-burn-through type paste; the process temperature of the sintering treatment is greater than the process temperature of the curing treatment.

[0020] In some embodiments, the first paste is a silver paste, and the second paste is a copper paste or a silver-coated copper paste.

[0021] In some embodiments, the solid content of the silver paste is 75% to 92%.

[0022] In some embodiments, the second surface also has a third printing area; the first paste is also printed on the third printing area in the step of performing the first screen printing process, and the main grid corresponding to the third printing area is also formed in the step of performing the sintering treatment; or, the second paste is also printed on the third printing area in the step of performing the second screen printing process, and the main grid corresponding to the third printing area is also formed in the step of performing the curing treatment.

[0023] In some embodiments, the fine grid formed on the second surface is a back fine grid, and the main grid formed on the second surface is a back main grid; the first surface has a fourth printing area extending along the first direction, and a fifth printing area extending along the second direction; before the sintering treatment, the manufacturing method of the photovoltaic cell also includes: using a third screen printing process to print a third paste on the fourth printing area; in the step of performing the sintering treatment, the third paste is also sintered to form a front fine grid corresponding to the fourth printing area; using a fourth screen printing process to print a fourth paste on the fifth printing area; in the step of performing the sintering treatment, the fourth paste is also sintered to form a front main grid corresponding to the fifth printing area.

[0024] According to some embodiments of the present disclosure, another aspect of the embodiments of the present disclosure further provides a stacked cell, comprising: a bottom cell, which is a photovoltaic cell as described in any one of the above items, or a photovoltaic cell formed by a manufacturing method of multiple photovoltaic cells as described in any one of the above items; and a top cell, which is located on one side of the bottom cell.

[0025] According to some embodiments of the present disclosure, on the other hand, the embodiments of the present disclosure further provide a photovoltaic assembly, comprising: a cell string, formed by connecting a plurality of photovoltaic cells as described in any one of the above items, or formed by connecting a plurality of photovoltaic cells formed by the photovoltaic cell manufacturing method as described in any one of the above items, or formed by connecting a plurality of stacked cells as described above; a packaging film for covering the surface of the cell string; and a cover plate for covering the surface of the packaging film facing away from the cell string.

[0026] The technical solution provided by the embodiments of the present disclosure has at least the following advantages:

[0027] The first contact portion is designed to be in contact with and connected to at least the first side portion and the second contact portion is in contact with and connected to the second side portion, or the second contact portion is designed to be in contact with and connected to at least the second side portion and the first contact portion is in contact with and connected to the first side portion, so that the first contact portion and the second contact portion adjacent to each other along the second direction are staggered in the first direction. In this way, on the one hand, under the premise that the size of the connection layer is the same, compared with preparing a contact structure with a long strip structure like the connection layer, the staggered arrangement of the first contact portion and the second contact portion is conducive to reducing the amount of material required for the contact structure while ensuring that the contact structure and the connection layer have sufficient contact area, thereby facilitating the improvement of the electrical connection performance between the gate line and the battery substrate and reducing the manufacturing cost of the gate line; on the other hand, the staggered arrangement of the first contact portion and the second contact portion is conducive to widening the distance between the two edges of the first contact portion and the second contact portion that are farthest apart in the first direction, thereby under the premise that the size of the connection layer is the same, compared with preparing a contact structure with a long strip structure like the connection layer, facilitating the reduction of the alignment accuracy requirement of the connection layer and the contact structure, thereby facilitating the reduction of the difficulty of preparing the connection layer and the gate line while ensuring high contact performance between the contact structure and the connection layer.

[0028] In addition, the material of the contact portion is designed to be different from the material of the connection layer. The cost of the material of the contact portion and the material of the connection layer can be adjusted to further reduce the manufacturing cost of the contact structure. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] One or more embodiments are exemplarily illustrated by the pictures in the corresponding drawings. These exemplified descriptions do not constitute a limitation on the embodiments. Unless otherwise stated, the pictures in the drawings do not constitute a scale limitation. In order to more clearly illustrate the embodiments of the present disclosure or the technical solutions in the traditional technology, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present disclosure. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0030] Figure 1 A first partial top view schematic diagram of a grid line in a photovoltaic cell provided by an embodiment of the present disclosure;

[0031] Figure 2 A partial top view schematic diagram of a photovoltaic cell provided by an embodiment of the present disclosure;

[0032] Figure 3 for Figure 2 A schematic cross-sectional view along a first cross-sectional direction AA1;

[0033] Figure 4 A second partial top view schematic diagram of a grid line in a photovoltaic cell provided by an embodiment of the present disclosure;

[0034] Figure 5 A third partial top view schematic diagram of a grid line in a photovoltaic cell provided by an embodiment of the present disclosure;

[0035] Figure 6 A fourth partial top view schematic diagram of a grid line in a photovoltaic cell provided by an embodiment of the present disclosure;

[0036] Figure 7 A fifth partial top view schematic diagram of a grid line in a photovoltaic cell provided by an embodiment of the present disclosure;

[0037] Figure 8 A partially enlarged schematic diagram of two adjacent contact portions in a photovoltaic cell provided by an embodiment of the present disclosure;

[0038] Figure 9 A sixth partial top view schematic diagram of a grid line in a photovoltaic cell provided by an embodiment of the present disclosure;

[0039] Figure 10 A seventh partial top view schematic diagram of a grid line in a photovoltaic cell provided by an embodiment of the present disclosure;

[0040] Figure 11 An eighth partial top view schematic diagram of a grid line in a photovoltaic cell provided by an embodiment of the present disclosure;

[0041] Figure 12 Another partial top view schematic diagram of a photovoltaic cell provided by an embodiment of the present disclosure;

[0042] Figure 13 A partial top view schematic diagram of a main grid in a photovoltaic cell provided in one embodiment of the present disclosure;

[0043] Figure 14 A partial cross-sectional schematic diagram of a laminated battery provided in yet another embodiment of the present disclosure;

[0044] Figure 15A partial three-dimensional schematic diagram of a cell string in a photovoltaic module provided by yet another embodiment of the present disclosure;

[0045] Figure 16 A partial cross-sectional schematic diagram of a photovoltaic assembly provided in yet another embodiment of the present disclosure.

[0046] Description of reference numerals:

[0047] 100, battery substrate; 110, first surface; 120, second surface; 101, grid line; 102, contact structure; 112, contact portion; 122, first contact portion; 122a, first edge; 1221, first portion; 1222, second portion; 132, second contact portion; 132a, second edge; 103, connecting layer; 113, first side; 123, second side; 104, fine grid; 105, main grid; 115, connecting structure; 125, interconnection layer; 135, connecting portion; 145, first connecting portion; 155, second connecting portion; 165, third side; 175, fourth side; 106, bottom battery; 107, top battery; 40, photovoltaic cell; 41, encapsulation film; 42, cover plate; 43, conductive tape. DETAILED DESCRIPTION

[0048] After analysis, it was found that whether it is a photovoltaic cell with grid lines on both sides or a back-contact cell with grid lines on one side, the amount of silver paste used in the process of forming grid lines by printing silver paste is large, the metallization cost is high, and the preparation cost of the grid lines needs to be reduced. Moreover, compared with photovoltaic cells with grid lines on both sides, the amount of silver paste used in the back-contact cell with grid lines on one side is greater.

[0049] In practical applications, for photovoltaic cells with grid lines on both sides, such as TOPCON cells, the amount of silver paste used for the entire photovoltaic cell is as high as 80 mg, and the amount of silver paste used for a single side is as high as 40 mg.

[0050] The embodiments of the present disclosure provide a photovoltaic cell and a method for manufacturing the same, a laminated cell, and a photovoltaic module. In the photovoltaic cell, the first contact portion is designed to be in contact and connected with at least the first side portion and the second contact portion is in contact and connected with the second side portion, or the second contact portion is designed to be in contact and connected with at least the second side portion and the first contact portion is in contact and connected with the first side portion, so that the first contact portion and the second contact portion adjacent to each other along the second direction can be staggered in the first direction. In this way, on the one hand, under the premise that the size of the connecting layer is the same, compared with preparing a contact structure with the same long strip structure as the connecting layer, the first contact portion and the second contact portion arranged in a staggered manner are conducive to reducing the amount of material required for the contact structure while ensuring that the contact structure and the connecting layer have sufficient contact area, thereby helping to improve the electrical connection performance between the gate line and the battery substrate and reduce the manufacturing cost of the gate line; on the other hand, with the help of the first contact portion and the second contact portion arranged in a staggered manner, it is conducive to widening the distance between the two edges of the first contact portion and the second contact portion that are farthest apart in the first direction, thereby under the premise that the size of the connecting layer is the same, compared with preparing a contact structure with the same long strip structure as the connecting layer, it is conducive to reducing the requirements for the alignment accuracy of the connecting layer and the contact structure, thereby helping to ensure high contact performance between the contact structure and the connecting layer while reducing the difficulty of preparing the connecting layer to reduce the difficulty of preparing the gate line. In addition, by designing the material of the contact portion to be different from the material of the connecting layer, the cost of the material of the contact portion and the material of the connecting layer can be adjusted to further reduce the manufacturing cost of the contact structure.

[0051] In the description of the embodiments of the present disclosure, technical terms such as "first" and "second" are used solely to distinguish between different objects and should not be understood to indicate or imply relative importance or to implicitly specify the quantity, specific order, or primary and secondary relationship of the technical features indicated. In the description of the embodiments of the present disclosure, "plurality" means more than two, unless otherwise specifically defined.

[0052] References herein to "embodiments" mean that a particular feature, structure, or characteristic described in connection with the embodiments may be included in at least one embodiment of the present disclosure. The appearance of this phrase in various places in the specification does not necessarily refer to the same embodiment, nor does it constitute an independent or alternative embodiment that is mutually exclusive of other embodiments. It is understood, both explicitly and implicitly, by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0053] In the description of the embodiments of the present disclosure, the term "and / or" is merely a description of an association relationship between associated objects, indicating that three relationships may exist. For example, A and / or B can represent the following three situations: A exists, A and B exist at the same time, and B exists. In addition, the character " / " in this document generally indicates that the associated objects are in an "or" relationship.

[0054] In the description of the embodiments of the present disclosure, the term "multiple" refers to more than two (including two). Similarly, "multiple groups" refers to more than two groups (including two groups), and "multiple pieces" refers to more than two pieces (including two pieces).

[0055] In the description of the embodiments of the present disclosure, the technical terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc., indicating the orientation or position relationship, are based on the orientation or position relationship shown in the accompanying drawings, and are only for the convenience of describing the embodiments of the present disclosure and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operate in a specific orientation, and therefore should not be understood as limiting the embodiments of the present disclosure.

[0056] In the description of the embodiments of the present disclosure, unless otherwise expressly specified or limited, technical terms such as "installed," "connected," "connected," and "fixed" should be understood in a broad sense. For example, they can refer to fixed connections, detachable connections, or integration; mechanical connections or electrical connections; direct connections or indirect connections through an intermediate medium; and they can refer to internal connectivity between two components or interaction between two components. Those skilled in the art can understand the specific meanings of the above terms in the embodiments of the present disclosure based on specific circumstances.

[0057] In the accompanying drawings corresponding to the embodiments of the present disclosure, the thickness and area of ​​layers are exaggerated for better understanding and ease of description. When a component (such as a layer, film, region, or substrate) is described as being on or on the surface of another component, the component may be "directly" located on the surface of the other component, or a third component may be present between the two components. Conversely, when a component is described as being on the surface of another component, or as being formed or disposed on the surface of one component, it indicates that there is no third component between the two components. Furthermore, when a component is described as being "substantially" formed on another component, this means that the component is not formed on the entire surface (or front surface) of the other component, nor is it formed on a portion of the edge of the entire surface.

[0058] In the description of the embodiments of the present disclosure, when a component is referred to as "including" another component, unless otherwise specified, this does not exclude other components, and other components may further be included. Furthermore, when a component such as a layer, film, region, or plate is referred to as being "on" another component, it may be "directly on" the other component (i.e., located on the surface of the other component with no other components between them) or another component may be present between them. Furthermore, when a component such as a layer, film, region, or plate is referred to as being "directly on" another component, or when a component such as a layer, film, region, or plate is located on the surface of another component, this means that no other components are located between them.

[0059] The terms used herein in the description of the various embodiments are intended only to describe the specific embodiments and are not intended to be limiting. As used in the description of the various embodiments and the appended claims, "the component" is intended to include the plural form unless the context clearly indicates otherwise. A component includes a layer, film, region, or plate.

[0060] The following describes various embodiments of the present disclosure in detail with reference to the accompanying drawings. However, those skilled in the art will appreciate that many technical details are provided in the various embodiments of the present disclosure to help readers better understand the embodiments of the present disclosure. However, even without these technical details and the various variations and modifications based on the following embodiments, the technical solutions claimed in the embodiments of the present disclosure can be implemented.

[0061] An embodiment of the present disclosure provides a photovoltaic cell, which will be described in detail below with reference to the accompanying drawings.

[0062] Combined with reference Figures 1 to 7The photovoltaic cell includes: a cell substrate 100 having a first surface 110 and a second surface 120 opposite to each other along a thickness direction Z; a plurality of grid lines 101 located on the first surface 110 and / or the second surface 120 and arranged at intervals along a first direction X; the grid lines 101 include a contact structure 102 electrically connected to the cell substrate 100 and a connection layer 103; the contact structure 102 includes a plurality of contact portions 112 sequentially arranged along a second direction Y; the connection layer 103 is a long strip structure extending along the second direction Y, and the first direction X and the second direction Y intersect; wherein the connection layer 103 and the contact structure 102 are electrically connected to each other. Multiple contact portions 112 in the structure 102 are in contact and connected, the material of the contact portion 112 is different from the material of the connecting layer 103, and the orthographic projections of the contact portion 112 and the connecting layer 103 on the battery substrate 100 partially overlap; the contact portion 112 includes a first contact portion 122 and a second contact portion 132 alternately arranged along the second direction Y, and the connecting layer 103 has a first side portion 113 and a second side portion 123 opposite to each other along the first direction X, the first contact portion 122 is in contact and connected to at least the first side portion 113, and the second contact portion 132 is in contact and connected to at least the second side portion 123.

[0063] in, Figure 1 A first partial top view schematic diagram of a grid line in a photovoltaic cell provided by an embodiment of the present disclosure; Figure 2 A partial top view schematic diagram of a photovoltaic cell provided by an embodiment of the present disclosure; Figure 3 for Figure 2 A schematic cross-sectional view along a first cross-sectional direction AA1; Figure 4 A second partial top view schematic diagram of a grid line in a photovoltaic cell provided by an embodiment of the present disclosure; Figure 5 A third partial top view schematic diagram of a grid line in a photovoltaic cell provided by an embodiment of the present disclosure; Figure 6 A fourth partial top view schematic diagram of a grid line in a photovoltaic cell provided by an embodiment of the present disclosure; Figure 7 This is a fifth partial top view schematic diagram of a grid line in a photovoltaic cell provided by an embodiment of the present disclosure.

[0064] It should be noted that, in order to clearly illustrate the positional relationship between the connecting layer 103 and the contact portion 112, Figure 1 and Figure 2 In the figure, the connection layer 103 is drawn in perspective. Figure 1 This is only an example of a positional relationship between the connecting layer 103 and the contact portion 112 , and the positional relationship between the connecting layer 103 and the contact portion 112 will be described in detail later with reference to other drawings. Figure 3 In the example, the gate line 101 is located on the second surface 120. In actual applications, the gate line can be located on the first surface, or on both the first surface and the second surface.

[0065] It is worth noting that in some cases, reference Figure 1 、 Figure 4 、 Figure 5 or Figure 6 The first contact portion 122 is designed to be in contact and connected with at least the first side portion 113, and the second contact portion 132 is designed to be in contact and connected with at least the second side portion 123, so that the first contact portions 122 and the second contact portions 132 adjacent to each other along the second direction Y are staggered in the first direction X. Alternatively, the first contact portion 122 is in contact and connected with at least the first side portion 113, and the second contact portion 132 is in contact and connected with the second side portion 123, or the second contact portion 132 is in contact and connected with at least the second side portion 123, and the first contact portion 122 is in contact and connected with the first side portion 113. It should be noted that the positional relationship between the contact portion 112 and the connection layer 103 in the contact structure 102 will be described in detail later.

[0066] In this way, on the one hand, under the premise that the size of the connecting layer 103 is the same, compared with preparing a contact structure with the same long strip structure as the connecting layer 103, the first contact portion 122 and the second contact portion 132 arranged in a staggered manner are beneficial to reducing the amount of material required for the contact structure 102 while ensuring that the contact structure 102 and the connecting layer 103 have sufficient contact area, thereby facilitating the improvement of the electrical connection performance between the gate line 101 and the battery substrate 100 and reducing the manufacturing cost of the gate line 101; on the other hand, along the first direction X, the first contact portion 122 has a third edge away from the second contact portion 132, and the second contact portion 132 has a fourth edge away from the first contact portion 122, and with the help of the staggered arrangement of the first contact portion 122 and the second contact portion 132, it is beneficial to By widening the spacing between the third edge and the fourth edge in the first direction X, under the premise that the size of the connecting layer 103 is the same, compared with preparing a contact structure with the same long strip structure as the connecting layer 103, it is beneficial to reduce the requirements for the alignment accuracy of the connecting layer 103 and the contact structure 102. In other words, based on the staggered arrangement of the first contact portion 122 and the second contact portion 132, a larger offset error in the first direction X between the connecting layer 103 and the contact structure 102 can be allowed, and within the offset error, the contact area between the connecting layer 103 and the contact structure 102 will not change, which is beneficial to further ensure higher contact performance between the contact structure 102 and the connecting layer 103, and reduce the difficulty of preparing the connecting layer 103 to reduce the difficulty of preparing the gate line 101.

[0067] In some examples, reference Figure 1 、 Figure 4 or Figure 5 The first contact portion 122 is in contact with at least the first side portion 113 and the second contact portion 132 is only in contact with the second side portion 123 . The second contact portion 132 is not in contact with the first side portion 113 .

[0068] In other examples, reference Figure 1 、 Figure 4 or Figure 6 The second contact portion 132 is in contact with at least the second side portion 123 , and the first contact portion 122 is only in contact with the first side portion 113 . The first contact portion 122 is not in contact with the second side portion 123 .

[0069] In other cases, refer to Figure 7 The first contact portion 122 is designed to be in contact and connected with at least the first side portion 113, and the second contact portion 132 is designed to be in contact and connected with at least the second side portion 123. The first contact portion 122 and the second contact portion 132 adjacent to each other in the second direction Y can also be arranged at intervals in the second direction Y, and the first contact portion 122 is in contact and connected with both the first side portion 113 and the second side portion 123, and the second contact portion 132 is also in contact and connected with both the first side portion 113 and the second side portion 123. In this way, under the premise that the size of the connection layer 103 is the same, compared with preparing a contact structure with the same long strip structure as the connection layer 103, by using the first contact portion 122 and the second contact portion 132 arranged at intervals in the second direction Y, it is beneficial to reduce the amount of material required for the contact structure 102 while ensuring that the contact structure 102 and the connection layer 103 have sufficient contact area, thereby improving the electrical connection performance between the gate line 101 and the battery substrate 100 and reducing the manufacturing cost of the gate line 101.

[0070] In addition, by designing the material of the contact portion 112 to be different from the material of the connecting layer 103, it is possible to avoid using the same material for the gate line 101. By adjusting the cost of the material of the contact portion 112 and the material of the connecting layer 103, for example, by designing the cost of the material of the connecting layer 103 to be lower than the cost of the material of the contact portion 112, the amount of material required for the contact structure 102 can be reduced with the help of the dispersed multiple contact portions 112, thereby reducing the preparation cost of the contact structure 102. At the same time, the preparation cost of the contact structure 102 can be further reduced based on the reduction in the cost of the material of the connecting layer 103.

[0071] It should be noted that in some cases, reference Figures 1 to 7For a single gate line 101, the connection layer 103 can be in contact with each contact portion 112 in the contact structure 102. In practical applications, due to limitations in the printing process, when the connection layer overlaps with the orthographic projection of each contact portion on the battery substrate, the connection layer may not form a good contact with each individual contact portion. For example, if there is a large error in the printing thickness of an individual contact portion or a large error in the printing thickness of a portion of the connection layer. Alternatively, due to limitations in the printing process, if the final pattern of an individual contact portion differs significantly from the designed pattern, the connection layer may not form a good contact with the contact portion.

[0072] The photovoltaic cell provided in one embodiment of the present disclosure will be described in more detail below with reference to the accompanying drawings.

[0073] In some embodiments, reference Figure 4 In the same gate line 101 , the first contact portion 122 and the second contact portion 132 are not directly opposite each other along the second direction Y. In other words, with the plane perpendicular to the second direction Y as the projection plane, the orthographic projections of the first contact portion 122 and the second contact portion 132 on the projection plane do not overlap.

[0074] In this case, the contact portion 112 and the connection layer 103 are in contact with each other as follows: the first contact portion 122 is in contact with the first side portion 113 only, and the second contact portion 132 is in contact with the second side portion 123 only.

[0075] In other embodiments, reference Figure 1 、 Figure 5 or Figure 6 In the same gate line 101, a partial area of ​​the first contact portion 122 and a partial area of ​​the second contact portion 132 are directly opposite each other along the second direction Y. In other words, with the plane perpendicular to the second direction Y as the projection plane, the orthographic projections of the first contact portion 122 and the second contact portion 132 on the projection plane partially overlap.

[0076] Thus, the contact connection between the contact portion 112 and the connection layer 103 includes at least the following three situations:

[0077] In some cases, reference Figure 1 The contact connection between the contact portion 112 and the connection layer 103 is as follows: the first contact portion 122 is only in contact with the first side portion 113, and the second contact portion 132 is only in contact with the second side portion 123. It should be noted that in order to reduce the size of the contact portion 112 itself to reduce the manufacturing cost, while increasing the contact area between the contact portion 112 and the connection layer 103, compared with Figure 4 Contact portion 112 is shown, Figure 1The contact portion 112 shown may have a larger width in the first direction X and a smaller extension length in the second direction Y, so as to ensure that more than half of the area of ​​the contact structure 102 can be in contact with the connection layer 103 as much as possible.

[0078] In other cases, refer to Figure 5 , the contact connection between the contact portion 112 and the connection layer 103 is as follows: the first contact portion 122 is in contact and connection with not only the first side portion 113 but also the second side portion 123, and the second contact portion 132 is in contact and connection with only the second side portion 123. It should be noted that in order to reduce the size of the contact portion 112 itself to reduce the manufacturing cost while increasing the contact area between the contact portion 112 and the connection layer 103, the width of the first contact portion 122 in the first direction X can be greater than the width of the second contact portion 132 in the first direction X, so as to ensure that more than half of the area in the contact structure 102 can be in contact and connection with the connection layer 103 as much as possible. In addition, compared to Figure 1 Contact portion 112 is shown, Figure 5 The contact portion 112 shown may have a larger width in the first direction X and a smaller extension length in the second direction Y, so as to minimize the amount of material required for the contact structure 102 .

[0079] In some cases, refer to Figure 6 , the contact connection between the contact portion 112 and the connection layer 103 is as follows: the first contact portion 122 is only in contact with the first side portion 113, and the second contact portion 132 is not only in contact with the second side portion 123 but also in contact with the first side portion 113. It should be noted that in order to reduce the size of the contact portion 112 itself to reduce the manufacturing cost while increasing the contact area between the contact portion 112 and the connection layer 103, the width of the second contact portion 132 in the first direction X can be greater than the width of the first contact portion 122 in the first direction X, so as to ensure that more than half of the area in the contact structure 102 can be in contact with the connection layer 103 as much as possible. In addition, compared to Figure 1 Contact portion 112 is shown, Figure 6 The contact portion 112 shown may have a larger width in the first direction X and a smaller extension length in the second direction Y, so as to minimize the amount of material required for the contact structure 102 .

[0080] In each of the above cases, refer to Figure 8 , Figure 8This is a partially enlarged schematic diagram of two adjacent contact portions in a photovoltaic cell provided by an embodiment of the present disclosure. Along the second direction Y, the portion of the first contact portion 122 that directly opposes the second contact portion 132 is the first portion 1221. The width S of the portion of the first contact portion 122 other than the first portion 1221 in the first direction X is less than or equal to 25 μm. In other words, the maximum misalignment difference between the adjacent first contact portion 122 and the second contact portion 132 along the second direction Y is less than or equal to 25 μm. For example, the maximum misalignment difference can be 24 μm, 23 μm, 22 μm, 21 μm, 20 μm, 19 μm, 18 μm, 17 μm, 16 μm, 15 μm, 14 μm, 13 μm, 12 μm, 11 μm, 10 μm, 9 μm, 8 μm, 7 μm, 6 μm, 5 μm, 4 μm, 3 μm, 2 μm, or 1 μm.

[0081] It should be noted that the portion of the first contact portion 122 other than the first portion 1221 may be the second portion 1222 , and the width S of the second portion 1222 in the first direction X is less than or equal to 25 μm. Figure 8 The first portion 1221 and the second portion 1222 of the first contact portion 122 are divided by a dotted line.

[0082] It is worth noting that, assuming that portions of the first contact portion 122 and portions of the second contact portion 132 are aligned along the second direction Y, if the width S of the second portion 1222 in the first direction X is greater than 25 μm, the offset between adjacent first and second contact portions 122, 132 in the first direction X will be relatively large, and the distance between the third and fourth edges in the first direction X will be too large. This, while maintaining the size of the connection layer 103, is detrimental to ensuring a large contact area between the connection layer 103 and the contact structure 102. Therefore, designing the offset between adjacent first and second contact portions 122, 132 along the second direction Y to be less than or equal to 25 μm facilitates controlling the offset between adjacent first and second contact portions 122, 132 in the first direction X to be appropriate, thereby minimizing the size of the contact portion 112 itself while ensuring that more than half of the contact structure 102 is in contact with the connection layer 103.

[0083] In some other embodiments, reference Figure 7 In the same gate line 101, the first contact portion 122 and the second contact portion 132 are directly opposite each other along the second direction Y. In other words, with the plane perpendicular to the second direction Y as the projection plane, the orthographic projections of the first contact portion 122 and the second contact portion 132 on the projection plane coincide with each other, that is, the misalignment difference between the adjacent first contact portion 122 and the adjacent second contact portion 132 along the second direction Y is zero.

[0084] In this case, the contact portions 112 and the connection layer 103 are in contact with each other as follows: the first contact portion 122 is in contact with both the first side portion 113 and the second side portion 123 , and the second contact portion 132 is in contact with both the first side portion 113 and the second side portion 123 .

[0085] The contact portion 112 will be described in detail below.

[0086] In some embodiments, reference Figures 1 to 8 , along the thickness direction Z, the orthographic projection shape of the contact portion 112 on the battery substrate 100 can be a rectangle.

[0087] In other embodiments, reference Figure 9 , Figure 9 This is a sixth partial top view of a grid line in a photovoltaic cell according to an embodiment of the present disclosure. In the thickness direction Z, the orthographic projection of the contact portion 112 on the cell substrate 100 may be a circle. It should be noted that, due to the influence of the process accuracy of forming the contact portion 112, when the orthographic projection of the contact portion 112 on the cell substrate 100 is a circle, the circle may be approximately circular and does not necessarily have to be a perfect circle in the geometric sense.

[0088] In some other embodiments, reference Figure 10 , Figure 10 This is a seventh partial top view of a grid line in a photovoltaic cell according to an embodiment of the present disclosure. In the thickness direction Z, the orthographic projection of the contact portion 112 onto the cell substrate 100 may be an ellipse. It should be noted that, due to the influence of the process accuracy of forming the contact portion 112, when the orthographic projection of the contact portion 112 onto the cell substrate 100 is an ellipse, the circular shape may also be an approximate ellipse, and does not necessarily have to be a standard ellipse in the geometric sense.

[0089] In some further embodiments, reference Figure 11 , Figure 11 This is an eighth partial top view schematic diagram of a grid line in a photovoltaic cell provided by an embodiment of the present disclosure. Along the thickness direction Z, the orthographic projection shape of the contact portion 112 on the cell substrate 100 can be a triangle.

[0090] It should be noted that, in practical applications, the orthographic projection shape of the contact portion on the battery substrate may also be a trapezoid or an N-gon, where N is a positive integer greater than 4.

[0091] In some embodiments, reference Figure 9Along the thickness direction Z, the orthographic projection of the contact portion 112 on the battery substrate 100 is circular or elliptical, and adjacent first and second contact portions 122, 132 are tangent to each other along the second direction Y. Thus, due to the special morphology of the contact portion 112, although adjacent first and second contact portions 122, 132 are partially in contact, the majority of the contact portions are spaced apart along the second direction Y. This also helps minimize the amount of material required for the contact structure 102 while maintaining the same dimensions of the connection layer 103.

[0092] It should be noted that Figure 9 For example, the orthographic projection of the contact portion 112 on the battery substrate 100 is circular, and the first contact portion 122 and the second contact portion 132 adjacent to each other along the second direction Y are tangent to each other. In practical applications, when the orthographic projection of the contact portion on the battery substrate is circular, the first contact portion and the second contact portion adjacent to each other along the second direction may also be spaced apart from each other.

[0093] In addition, when the orthographic projection of the contact portion on the battery substrate is an ellipse, the first contact portion and the second contact portion adjacent to each other along the second direction may also be tangent to each other. Figure 10 It is merely taken as an example that the orthographic projection shape of the contact portion 112 on the battery substrate 100 is an ellipse, and the first contact portion 122 and the second contact portion 132 adjacent to each other along the second direction Y are spaced apart from each other.

[0094] In some embodiments, in conjunction with reference Figures 1 to 11 , along the thickness direction Z, the orthographic projection area of ​​the contact portion 112 on the battery substrate 100 can be 100 μm 2 ~5000μm 2 , for example, can be 300 μm 2 , 500μm 2 , 800μm 2 , 1000μm 2 , 1200μm 2 , 1500μm 2 , 1700μm 2 , 2000μm 2 , 2300μm 2 , 2500μm 2 , 2800μm 2 , 3000μm 2 , 3300μm 2 , 3500μm 2 , 3800μm 2 , 4000μm 2 , 4200μm 2 , 4500μm 2 or 4800 μm 2 wait.

[0095] It is worth noting that if the orthographic projection area of ​​the contact portion 112 on the battery substrate 100 is less than 100 μm 2 If the contact area between a single contact portion 112 and the connecting layer 103 is too small, it is not conducive to improving the electrical connection performance between the contact portion 112 and the battery substrate 100, nor is it conducive to improving the contact performance between the contact portion 112 and the connecting layer 103; if the orthographic projection area of ​​the contact portion 112 on the battery substrate 100 is greater than 5000 μm 2 The effect of reducing the amount of material required for the contact structure 102 by simply relying on the spacing between adjacent contact portions 112 is limited. Thus, the orthographic projection area of ​​the contact portion 112 on the battery substrate 100 can be designed to be 100 μm 2 ~5000μm 2 This is beneficial for improving the electrical connection performance between the contact portion 112 and the battery substrate 100, and improving the contact performance between the contact portion 112 and the connection layer 103, while reducing the amount of material required for the contact structure 102 as much as possible.

[0096] In some embodiments, reference Figures 1 to 7 or Figures 9 to 11 Along the first direction X, the width of the connection layer 103 can be 10μm~70μm, for example, 15μm, 20μm, 25μm, 30μm, 35μm, 40μm, 45μm, 50μm, 55μm, 60μm or 65μm, etc.

[0097] In some cases, reference Figure 1 Along the first direction X, the width of the connecting layer 103 can be basically the same as the width of the contact portion 112. The difference is that the multiple contact portions 112 in the contact structure 102 along the second direction Y are staggered in the first direction X, and the connecting layer 103 is a long strip structure extending along the second direction Y.

[0098] In some embodiments, reference Figure 8 In the first contact portion 122 and the second contact portion 132 adjacent to each other along the second direction Y, the edge of the first contact portion 122 closest to the second contact portion 132 is the first edge 122a, and the edge of the second contact portion 132 closest to the first contact portion 122 is the second edge 132a, and the distance D between the first edge 122a and the second edge 132a is less than or equal to 200 μm.

[0099] It is worth noting that if the distance D between the first edge 122a and the second edge 132a is greater than 200 μm, the arrangement spacing between adjacent first contact portions 122 and second contact portions 132 is large, so that the arrangement density of the contact portions 112 in the contact structure 102 is too low, which will cause the connection layer 103 (refer to Figure 1 ) are not in contact with the contact structure 102 (reference Figure 1 ) contact connection. Designing the distance D between the first edge 122a and the second edge 132a to be less than or equal to 200 μm helps ensure a high density of contact portions 112 in the contact structure 102, thereby ensuring that most areas of the connection layer 103 can be in contact with the contact structure 102, thereby ensuring sufficient contact area between the connection layer 103 and the contact structure 102.

[0100] It should be noted that Figure 8 The distance D between the first edge 122a and the second edge 132a is shown in the figure using the orthographic projection of the contact portion 112 on the battery substrate 100 as an example, which is a rectangle. In practical applications, when the orthographic projection of the contact portion on the battery substrate has other shapes, the distance between the first edge and the second edge may also be less than or equal to 200 μm.

[0101] In some embodiments, in conjunction with reference Figures 1 to 11 Along the thickness direction Z, the thickness of the contact portion 112 may be 1 μm to 10 μm, for example, 2 μm, 3 μm, 4 μm, 5 μm, 6 μm, 7 μm, 8 μm or 9 μm.

[0102] In some embodiments, in conjunction with reference Figures 1 to 11 The thickness of the connecting layer 103 can be 4μm~20μm, for example, it can be 5μm, 6μm, 7μm, 8μm, 9μm, 10μm, 11μm, 12μm, 13μm, 14μm, 15μm, 16μm, 17μm, 18μm or 19μm, etc.

[0103] The material of the contact portion 112 and the material of the connection layer 103 are described in detail below.

[0104] In some embodiments, in conjunction with reference Figures 1 to 11 The material of the contact portion 112 may include silver particles, and the material of the connection layer 103 may include copper particles or silver-coated copper particles.

[0105] It is worth noting that, per unit mass, the cost of silver particles is higher than that of copper particles, and also higher than that of silver-coated copper particles. In addition, the electrical connection performance between silver particles and the battery substrate 100 is higher than that between copper particles and the battery substrate 100, and also higher than that between silver-coated copper particles and the battery substrate 100. Based on this, designing the material of the contact structure in the grid line 101 to be silver particles, on the one hand, is conducive to greatly reducing the content of silver particles in the grid line 101 while maximally ensuring the electrical connection performance between the grid line 101 and the battery substrate 100, thereby ensuring that the photovoltaic cell has a high photoelectric conversion efficiency. On the other hand, compared with the amount of slurry required by the contact structure 102, the connection layer 103, which requires a larger amount of slurry, is designed to include copper particles or silver-coated copper particles. This ensures that the amount of connection layer 103 is sufficient, so that the connection layer 103 can effectively collect carriers from the multiple contact portions 112 in the contact structure 102, and also reduces the preparation cost of forming the connection layer 103.

[0106] In some cases, compared to forming gate lines on the first or second surface using only silver paste, if only the material of the contact portion 112 of the gate line 101 includes silver particles, that is, only silver paste is used to form the contact portion 112, the amount of silver paste required to form the contact portion 112 can be lower, for example, it can be reduced to 3mg-15mg. In other words, compared to forming gate lines on the first or second surface using only silver paste, the amount of silver paste used on a single side can be as high as 40mg. In the gate line 101 designed in one embodiment of the present disclosure, the amount of silver paste used on a single side can be reduced to 3mg-15mg.

[0107] It should be noted that, in the gate line 101 designed in one embodiment of the present disclosure, in addition to designing the first contact portion 122 and the second contact portion 132 to be staggered in the first direction X to reduce the amount of silver paste required for forming the contact portion 112, the amount of silver paste required for forming the contact portion 112 can also be further reduced by reducing the thickness of the contact portion 112 in the thickness direction Z.

[0108] In some cases, in conjunction with reference Figures 1 to 11 The material of the connecting layer 103 may include copper particles, and the diameter of the copper particles may be 50nm~1500nm, for example, 100nm, 200nm, 300nm, 400nm, 500nm, 600nm, 700nm, 800nm, 900nm, 1000nm, 1100nm, 1200nm, 1300nm or 1400nm, etc.

[0109] In other cases, in conjunction with Figures 1 to 11The material of the connecting layer 103 may include silver-coated copper particles, and the diameter of the silver-coated copper particles may be 1μm~10μm, for example, it may be 100nm, 200nm, 300nm, 400nm, 500nm, 600nm, 700nm, 800nm, 900nm, 1000nm, 1100nm, 1200nm, 1300nm or 1400nm, etc.

[0110] It should be noted that the diameter of the silver-coated copper particle refers to the outer diameter of the silver-coated copper particle, that is, the diameter of the entire outer contour of the silver-coated copper particle.

[0111] In some examples, the proportion of silver in the silver-coated copper particles is 15% to 50%, for example, it can be 16%, 17%, 18%, 19%, 20%, 21%, 22%, 23%, 24%, 25%, 26%, 27%, 28%, 29%, 30%, 31%, 32%, 33%, 34%, 35%, 36%, 37%, 38%, 39%, 40%, 41%, 42%, 43%, 44%, 45%, 46%, 47%, 48% or 49%, etc.

[0112] The types of the gate lines 101 are described in detail below.

[0113] In some embodiments, reference Figure 12 , Figure 12 This is another partial top view of a photovoltaic cell provided by an embodiment of the present disclosure, wherein the grid line 101 is one of the fine grid 104 and the main grid 105, and the other of the fine grid 104 and the main grid 105 is a long strip structure extending along the first direction X. It should be noted that, Figure 12 In the example, the gate line 101 is a fine gate 104 and the main gate 105 is a long strip structure extending along the first direction X. In actual applications, the gate line can also be a main gate and the fine gate can be a long strip structure extending along the first direction.

[0114] It is worth noting that whether the fine grid 104 or the main grid 105 adopts the design of the grid line 101 described in the various embodiments above, it is beneficial to improve the electrical connection performance between the grid line 101 and the battery substrate 100 and reduce the manufacturing cost of the grid line 101. In addition, the staggered design of the contact portion 112 in the grid line 101 is beneficial to reducing the difficulty of preparing the grid line 101.

[0115] Furthermore, on the cell substrate 100, the arrangement density of the fine grids 104 is greater than the arrangement density of the busbars 105. Consequently, the total amount of material required to prepare all the fine grids 104 on a single surface is generally greater than the total amount of material required to prepare all the busbars 105 on a single surface. Furthermore, adopting the design of the grid lines 101 described in the various embodiments described above as compared to ...

[0116] Furthermore, in some cases, the fine grid 104 needs to be electrically connected to the cell substrate 100, while the busbar 105 can be connected only to the fine grid 104, without the need for the busbar 105 to be electrically connected to the cell substrate 100. Carriers in the cell substrate 100 can be first collected by the fine grid 104, and then collected by the busbar 105, which is in contact with the fine grid 104. In this way, the material used to form the busbar 105 does not need to achieve direct electrical connection between the busbar 105 and the cell substrate 100. For example, the material used to form the busbar 105 does not need to be embedded in the passivation layer of the cell substrate 100. Therefore, a lower-cost material can be selected for the busbar 105 to achieve contact connection between the busbar 105 and the fine grid 104. On this basis, the fine grid 104 adopts the design of the grid line 101 described in the various embodiments above, which is not only beneficial to promote the electrical contact performance between the fine grid 104 and the battery substrate 100 with the help of the contact structure 102, but also beneficial to reduce the preparation cost of the fine grid 104 with the help of the connecting layer 103. Moreover, the main grid 105 can choose a lower cost material to further reduce the preparation cost of the photovoltaic cell.

[0117] It should be noted that Figures 1 to 12 In the example, a single first contact portion 122 and a single second contact portion 132 are staggered in the first direction X along the second direction Y. In other words, Figures 1 to 12 In the example shown, among the multiple contact portions 112 connected to the same connection layer 103 , along the second direction Y, only one second contact portion 132 is spaced between two adjacent first contact portions 122 , and only one first contact portion 122 is spaced between two adjacent second contact portions 132 .

[0118] In practical applications, when designing adjacent first and second contact portions along the second direction with staggered arrangement in the first direction, there is no restriction on the number of second contact portions between two adjacent first contact portions, and for example, two or three can be provided. There is also no restriction on the number of first contact portions between two adjacent second contact portions, and for example, two or three can be provided. In other words, in practical applications, there may not be a second contact portion between two adjacent first contact portions along the second direction, or there may not be a first contact portion between two adjacent second contact portions along the second direction. For example, one first contact portion and three second contact portions may constitute an arrangement group, and multiple arrangement groups may be repeatedly arranged along the second direction.

[0119] In other embodiments, in combination with reference Figure 1 and Figure 13 , Figure 13 A partial top view of a main grid in a photovoltaic cell provided by an embodiment of the present disclosure, wherein the grid line 101 is a fine grid, and the photovoltaic cell may further include: Figure 3 ) and the second surface 120 (reference Figure 3 ) and arranged at intervals along the second direction Y, the busbars 105 include a connection structure 115 electrically connected to the battery substrate 100 and an interconnection layer 125, the connection structure 115 includes a plurality of connection portions 135 arranged in sequence along the first direction X, and the interconnection layer 125 is a long strip structure extending along the first direction X; wherein, the interconnection layer 125 is in contact with and connected to the plurality of connection portions 135 in the connection structure 115, the connection portions 135 include first connection portions 145 and second connection portions 155 alternately arranged along the second direction Y, the interconnection layer 125 has a third side portion 165 and a fourth side portion 175 opposite to each other along the first direction X, the first connection portion 145 is in contact with and connected to the third side portion 165, the second connection portion 155 is in contact with and connected to the fourth side portion 175, and the material of the connection portion 135 is different from that of the interconnection layer 125.

[0120] It is noteworthy that not only do the fine grids include contact structures 102 electrically connected to the cell substrate 100, but the busbar 105 also includes connection structures 115 electrically connected to the cell substrate 100. In other words, not only are portions of the fine grids directly electrically connected to the cell substrate 100, but portions of the busbar 105 are also directly electrically connected to the cell substrate 100. Consequently, carriers in the cell substrate 100 can be collected not only first via the fine grids and then via the busbar 105, but can also be collected directly by the busbar 105 with the aid of the connection structures 115. This helps shorten the transmission distance for some carriers in the cell substrate 100 to reach the busbar 105, thereby reducing carrier transmission losses. This helps improve the carrier collection efficiency of the busbar 105, thereby enhancing the photoelectric conversion efficiency of the photovoltaic cell.

[0121] It should be noted that the connection structure 115 in the main gate 105 is similar to the contact structure 102 in the fine gate. The connection portion 135 included in the connection structure 115 is similar to the contact portion 112 in the contact structure 102. The first connection portion 145 is similar to the first contact portion 122. The second connection portion 155 is similar to the second contact portion 132. The interconnection layer 125 is similar to the connection layer 103. The third side portion 165 is similar to the first side portion 113. The fourth side portion 175 is similar to the second side portion 123. The difference is that the specific size of the connection portion 135 is different from the specific size of the contact portion 112, and the specific size of the interconnection layer 125 is different from the specific size of the connection layer 103. The connection structure 115 and the interconnection layer 125 included in the main gate 105 are not described in detail here. In addition, Figure 13 Only one contact connection between the connection structure 115 and the interconnection layer 125 in the main gate 105 is illustrated. For other contact connection between the connection structure 115 and the interconnection layer 125 , reference may be made to the contact connection between the aforementioned contact structure and the connection layer.

[0122] The types of photovoltaic cells are described in detail below.

[0123] In some embodiments, the photovoltaic cell is a photovoltaic cell having grid lines on both sides, and can be, for example, a PERC cell, a TOPCON cell, a HIT / HJT cell (heterojunction technology cell), or a thin-film solar cell, or any combination thereof. The thin-film solar cell includes, but is not limited to, a perovskite thin-film solar cell, a copper indium selenide thin-film solar cell, a gallium arsenide thin-film solar cell, or a cadmium sulfide thin-film solar cell.

[0124] On this basis, reference Figure 3 The first surface 110 of the battery substrate 100 can be the front surface, and has a plurality of front fine grids (not shown in the figure) arranged at intervals along the first direction X, and a plurality of front main grids (not shown in the figure) arranged at intervals along the second direction Y; the second surface 120 of the battery substrate 100 can be the back surface, and has a plurality of back fine grids (not shown in the figure) arranged at intervals along the first direction X, and a plurality of back main grids (not shown in the figure) arranged at intervals along the second direction Y.

[0125] It should be noted that the photovoltaic cell can be a single-sided cell, that is, the first side 110 can serve as the light-receiving surface for receiving incident light, and the second side 120 can serve as the backlight surface; alternatively, the photovoltaic cell can be a bifacial cell, in which case both the first side 110 and the second side 120 can serve as the light-receiving surface, both of which can be used to receive incident light. It is understood that the backlight surface described in one embodiment of the present disclosure is also capable of receiving incident light, but the degree of reception of the incident light is weaker than that of the light-receiving surface, and therefore is defined as the backlight surface.

[0126] In some cases, reference Figure 3 The back fine grid can be the grid line 101 described in the various embodiments above, and the back main grid, the front fine grid and the front main grid can all be single-layer long strip structures. In this way, the preparation cost of the photovoltaic cell can be reduced with the help of the grid line 101 located on the second surface 120, while avoiding excessive obstruction of the cell substrate 100 by the front main grid and the back main grid located on the first surface, so as to ensure that the photovoltaic cell has a sufficient light-receiving surface.

[0127] In other cases, both the back side fine grid and the front side fine grid can be the grid lines 101 described in the above various embodiments (refer to Figures 1 to 11 ), both the back main grid and the front main grid can be a single layer long strip structure, or both the back main grid and the front main grid can be the main grid 105 described above (refer to Figure 13 ).

[0128] In some other cases, the back side fine grid may be the grid line 101 described in the above various embodiments (refer to Figures 1 to 11 ), the back main grid can be the main grid 105 described above (refer to Figure 13 ), both the front fine grid and the front main grid can be a single-layer long strip structure.

[0129] In some other cases, the front fine grid may be the grid line 101 described in the various embodiments above (see Figures 1 to 11 ), the front main grid can be the main grid 105 described above (refer to Figure 13 ), both the back fine grid and the back main grid can be a single-layer long strip structure.

[0130] In other embodiments, the photovoltaic cell is a back contact cell, i.e., a BC cell, including but not limited to an IBC cell (Interdigitated Back Contact), an HBC cell (Heterojunction Back Contact), a TBC cell (TOPCon Back Contact, referring to a cross-passivated back contact cell), or an HPBC cell (Hybrid Passivated Back Contact, a composite passivated back contact cell). Figure 3 The first surface 110 or the second surface 120 can be regarded as the back side of the photovoltaic cell finally formed.

[0131] On this basis, the back side of the photovoltaic cell includes a back fine grid and a back main grid.

[0132] In some cases, the backside fine grid located on the first surface or the second surface may be the grid line 101 described in the various embodiments above (refer to Figures 1 to 11 ), the back main grid can be a single-layer long strip structure.

[0133] In other cases, the backside fine grid located on the first surface or the second surface may be the grid line 101 described in the various embodiments above (refer to Figures 1 to 11 ), the back main grid located on the first surface or the second surface may be the main grid 105 described above (refer to Figure 13 ).

[0134] In summary, the first contact portion 122 and the second contact portion 132 adjacent to each other along the second direction Y in the contact structure 102 can be staggered in the first direction X. In this way, on the one hand, under the premise that the size of the connection layer 103 is the same, compared with preparing a contact structure with the same long strip structure as the connection layer 103, the staggered arrangement of the first contact portion 122 and the second contact portion 132 is beneficial to reducing the amount of material required for the contact structure 102 while ensuring that the contact structure 102 and the connection layer 103 have sufficient contact area, thereby facilitating the improvement of the electrical connection performance between the gate line 101 and the battery substrate 100 and reducing the manufacturing cost of the gate line 101; on the other hand, along the first direction X, the first contact portion 122 has a third edge away from the second contact portion 132, and the second contact portion 132 has a fourth edge away from the first contact portion 122. With the staggered arrangement of the first contact portion 122 and the second contact portion 132, it is beneficial to By widening the spacing between the third edge and the fourth edge in the first direction X, under the premise that the size of the connecting layer 103 is the same, compared with preparing a contact structure with the same long strip structure as the connecting layer 103, it is beneficial to reduce the requirements for the alignment accuracy of the connecting layer 103 and the contact structure 102. In other words, based on the staggered arrangement of the first contact portion 122 and the second contact portion 132, a larger offset error in the first direction X between the connecting layer 103 and the contact structure 102 can be allowed, and within the offset error, the contact area between the connecting layer 103 and the contact structure 102 will not change, which is beneficial to further ensure higher contact performance between the contact structure 102 and the connecting layer 103, and reduce the difficulty of preparing the connecting layer 103 to reduce the difficulty of preparing the gate line 101.

[0135] Another embodiment of the present disclosure further provides a method for manufacturing a photovoltaic cell, which is used to prepare the photovoltaic cell provided in the aforementioned embodiment. The method for manufacturing a photovoltaic cell provided in another embodiment of the present disclosure will be described in detail below with reference to the accompanying drawings. It should be noted that parts that are identical or corresponding to the aforementioned embodiments are not described in detail here.

[0136] Combined with reference Figures 1 to 11The manufacturing method of a photovoltaic cell includes: providing a cell substrate 100, the cell substrate 100 having a first surface 110 and a second surface 120 opposite to each other along a thickness direction Z; forming a plurality of grid lines 101 arranged at intervals along a first direction X on the first surface 110 and / or the second surface 120, the grid lines 101 including a contact structure 102 electrically connected to the cell substrate 100 and a connection layer 103, the contact structure 102 including a plurality of contact portions 112 sequentially arranged along a second direction Y, the connection layer 103 being a long strip structure extending along the second direction Y, the first surface 110 and / or the second surface 120 being arranged at intervals along a first direction X, The connecting layer 103 is in contact with and connected to a plurality of contact portions 112 in the contact structure 102, and the contact portions 112 include first contact portions 122 and second contact portions 132 alternately arranged along the second direction Y. The connecting layer 103 has a first side portion 113 and a second side portion 123 opposite to each other along the first direction X. The first contact portion 122 is in contact with and connected to at least the first side portion 113, and the second contact portion 132 is in contact with and connected to at least the second side portion 123. The material of the contact portion 112 is different from the material of the connecting layer 103.

[0137] In some cases, reference Figure 1 、 Figure 4 、 Figure 5 or Figure 6 The first contact portion 122 is designed to be in contact with and connected to at least the first side portion 113, and the second contact portion 132 is designed to be in contact with and connected to at least the second side portion 123, so that the first contact portions 122 and the second contact portions 132 adjacent to each other along the second direction Y are staggered in the first direction X. Alternatively, the second contact portion 132 is designed to be in contact with and connected to at least the second side portion 123, and the first contact portion 122 is designed to be in contact with and connected to the first side portion 113.

[0138] In other cases, refer to Figure 7 The first contact portion 122 is designed to be in contact and connected with at least the first side portion 113, and the second contact portion 132 is designed to be in contact and connected with at least the second side portion 123. The first contact portions 122 and the second contact portions 132 adjacent to each other in the second direction Y can also be arranged at intervals in the second direction Y, and the first contact portion 122 is in contact and connected with both the first side portion 113 and the second side portion 123, and the second contact portion 132 is also in contact and connected with both the first side portion 113 and the second side portion 123.

[0139] It is worth noting that dividing the contact portion 112 in the contact structure 102 into a first contact portion 122 that is in contact and connected with at least the first side portion 113, and a second contact portion 132 that is in contact and connected with at least the second side portion 123 is beneficial to reducing the amount of material required for the contact structure 102 while ensuring that the contact structure 102 and the connecting layer 103 have sufficient contact area by adjusting the positional relationship between the first contact portion 122 and the second contact portion 132 and the connecting layer 103, thereby improving the electrical connection performance between the gate line 101 and the battery substrate 100 and reducing the manufacturing cost of the gate line 101.

[0140] The following is a detailed description of the preparation process of the gate line 101.

[0141] In some embodiments, in conjunction with reference Figure 2 and Figure 3 The grid lines 101 can be fine grids; the second surface 120 has a first printed area (not labeled in the figure) and a second printed area (not labeled in the figure) that at least partially overlaps with the first printed area. It should be noted that the first printed area corresponds to the contact structure 102 to be formed later, and the second printed area corresponds to the connection layer 103 to be formed later. In other words, the first printed area is essentially the orthographic projection of the contact structure 102 to be formed later on the battery substrate 100, and the second printed area is essentially the orthographic projection of the connection layer 103 to be formed later on the battery substrate 100.

[0142] Continue to combine references Figure 2 and Figure 3 The steps of forming the gate line 101 may include: using a first screen printing process to print a first paste on a first printing area; sintering the first paste to form a contact structure 102 corresponding to the first printing area; using a second screen printing process to print a second paste on the second surface 120; curing the second paste to form a connection layer 103 corresponding to the second printing area; wherein the first paste is a burn-through paste and the second paste is a non-burn-through paste; the process temperature of the sintering treatment is greater than the process temperature of the curing treatment.

[0143] It is worth noting that since the first slurry is a burn-through type slurry and the second slurry is a non-burn-through type slurry, the contact structure 102 finally formed will be electrically connected to the battery substrate 100, for example, embedded in the passivation layer of the battery substrate 100, but the connecting layer 103 is only located on the surface of the battery substrate 100, that is, it will not be embedded in the passivation layer of the battery substrate 100, nor will it be directly electrically connected to the battery substrate 100.

[0144] In some cases, the first paste can be silver paste, and the second paste can be copper paste or silver-coated copper paste. In practical applications, based on the alternating design of the first contact portions 122 and the second contact portions 132 in the contact structure 102, the unit consumption of the first paste for a large surface can be reduced to 3mg-15mg, for example, 4mg, 5mg, 6mg, 7mg, 8mg, 9mg, 10mg, 11mg, 12mg, 13mg, or 14mg.

[0145] In some examples, the solid content of the silver paste can be 75% to 92%, for example, 76%, 77%, 78%, 79%, 80%, 81%, 82%, 83%, 84%, 85%, 86%, 87%, 88%, 89%, 90% or 91%, etc.

[0146] It is worth noting that the solids in the silver paste include not only silver particles but also at least glass. The solid content in the silver paste refers to the total content of all solids in the silver paste including the silver particles.

[0147] In some cases, in the process of forming the entire grid line by printing silver paste, the solid content of the silver paste used is generally large, for example, greater than 90%. Based on this, compared to the process of forming the entire grid line by printing silver paste, the solid content of the silver paste used in the photovoltaic cell manufacturing method provided by another embodiment of the present disclosure can be lower, and the silver paste used to form the contact structure 102 is thinner. In other words, the viscosity of the silver paste used to form the contact structure 102 is lower. In this way, when the silver paste is printed on the first printing area of ​​the battery substrate 100, the silver paste can have a certain degree of spreading on the battery substrate 100, which is convenient for increasing the contact area between the contact structure 102 formed subsequently based on the silver paste and the battery substrate 100.

[0148] It should be noted that the above-mentioned second surface 120 can be understood as the back side of the photovoltaic cell. In combination with the first screen printing process and the second screen printing process, a grid line 101 including a contact structure 102 and a connecting layer 103 can be formed on the second surface 120. In addition, the above-mentioned example of forming the grid line 101 on the second surface 120 is used. In actual applications, the first screen printing process and the second screen printing process can also be applied on the first surface to form the grid line on the first surface, which will not be described in detail here. Moreover, the above-mentioned example of the grid line 101 formed on the second surface 120 as a fine grid is used. In actual applications, the grid line combined with the first screen printing process and the second screen printing process can also be a main grid, and the grid line serving as the main grid can be formed on the first surface or the second surface, which will not be described in detail here.

[0149] It is worth noting that the reference Figure 13 , in the design of the main grid 105 including the battery substrate 100 (reference Figure 2) When the connection structure 115 and the interconnection layer 125 are electrically connected, the formation process of the connection structure 115 is similar to that of the contact structure 102 (refer to Figures 1 to 11 ) is similar to the formation process of the interconnection layer 125, and the formation process of the connection layer 103 is similar to that of the connection layer 103. Figures 1 to 11 ) is similar in formation process and will not be described here.

[0150] The following is a detailed description of the process of preparing the busbar 105 located on the second surface 120 except for the gate line 101 .

[0151] In some cases, reference Figure 2 The second surface 120 also has a third printed area (not shown). During the first screen printing process, the first paste is printed on the third printed area, and during the sintering process, a busbar corresponding to the third printed area is formed. It should be noted that the third printed area corresponds to the busbar formed subsequently. In other words, the third printed area is essentially the orthographic projection of the subsequently formed busbar on the battery substrate 100.

[0152] It is worth noting that the preparation of the contact structure 102 in the gate line 101 can be completed in the same step as the preparation of the main grid, which is beneficial to reduce one printing process and further reduce the preparation cost of the photovoltaic cell.

[0153] In other cases, refer to Figure 2 The second surface 120 further has a third printing area (not shown in the figure); in the step of performing the second screen printing process, a second paste is printed on the third printing area, and in the step of performing the curing process, a main grid 105 corresponding to the third printing area is formed (refer to Figure 12 It should be noted that the third printing area corresponds to the busbar 105 formed subsequently. In other words, the third printing area is basically the orthographic projection of the busbar 105 formed subsequently on the battery substrate 100 .

[0154] It is worth noting that the preparation of the connection layer 103 in the grid line 101 can be completed in the same step as the preparation of the main grid 105, which is also beneficial to reduce one printing process and further reduce the preparation cost of the photovoltaic cell.

[0155] In some other cases, the first screen printing process and sintering treatment are combined to form only the contact structure in the gate line; the second screen printing process and curing treatment are combined to form only the connection layer in the gate line, and other processes are subsequently used to form the main gate located on the second surface.

[0156] In the above cases, combined with reference Figure 3 and Figure 12The fine grids 104 formed on the second surface 120 may be back-surface fine grids, and the busbars 105 formed on the second surface 120 may be back-surface busbars. The first surface 110 has a fourth printed area (not shown) extending along the first direction X, and a fifth printed area (not shown) extending along the second direction Y. It should be noted that the fourth printed area corresponds to the subsequently formed front-surface fine grids, and the fifth printed area corresponds to the subsequently formed front-surface busbars. In other words, the fourth printed area is essentially the orthographic projection of the subsequently formed front-surface fine grids onto the battery substrate 100, and the fifth printed area is essentially the orthographic projection of the subsequently formed front-surface busbars onto the battery substrate 100.

[0157] Before performing the sintering treatment, the manufacturing method of the photovoltaic cell may also include: using a third screen printing process to print a third paste on the fourth printing area; in the step of performing the sintering treatment, the third paste is also sintered to form a front fine grid corresponding to the fourth printing area; using a fourth screen printing process to print a fourth paste on the fifth printing area; in the step of performing the sintering treatment, the fourth paste is also sintered to form a front main grid corresponding to the fifth printing area.

[0158] In some examples, the third paste and the fourth paste may be the same, that is, the material of the front fine grid and the material of the front bus bar may be the same.

[0159] It should be noted that the order of the third screen printing process and the fourth screen printing process can be swapped.

[0160] Based on the above description, it can be seen that when the back side fine grid is used as the grid line 101, the printing process of the photovoltaic cell includes at least the following situations: in some cases, the back main grid, the contact structure 102 in the grid line 101, the front main grid and the front fine grid can be formed by four printing processes respectively, and then they are sintered uniformly, and finally the connection layer 103 in the grid line 101 is printed and cured; in other cases, the back main grid and the contact structure 102 in the grid line 101 are formed by the same printing process, and the front main grid and the front fine grid can be formed by two printing processes respectively, and then they are sintered uniformly, and finally the connection layer 103 in the grid line 101 is printed and cured; in some other cases, the contact structure 102 in the grid line 101, the front main grid and the front fine grid can be formed by three printing processes respectively, and then they are sintered uniformly, and the back main grid and the connection layer 103 in the grid line 101 are formed by the same printing process, and finally they are cured.

[0161] Another embodiment of the present disclosure provides a laminated cell, comprising the photovoltaic cell provided in the preceding embodiments, or a photovoltaic cell formed by the photovoltaic cell manufacturing method provided in the preceding embodiments. The laminated cell provided in another embodiment of the present disclosure will be described in detail below with reference to the accompanying drawings. It should be noted that parts identical or corresponding to the preceding embodiments will not be repeated here.

[0162] refer to Figure 14 , Figure 14 A partial cross-sectional schematic diagram of a laminated solar cell provided in yet another embodiment of the present disclosure includes: a bottom cell 106, which is the photovoltaic cell provided in the aforementioned embodiment, or a photovoltaic cell formed by the photovoltaic cell manufacturing method provided in the aforementioned embodiment; and a top cell 107, which is located on one side of the bottom cell 106.

[0163] In some embodiments, the top cell 107 may be one of a perovskite solar cell, a donor-acceptor cell, a cadmium telluride (CdTe) solar cell, a copper indium gallium selenide (CIGS) solar cell, or a gallium arsenide (GaAs) solar cell.

[0164] In some embodiments, the top cell 107 may include: a stacked first transmission layer, a perovskite substrate, a second transmission layer, a transparent conductive layer, and an anti-reflection layer, wherein the first transmission layer faces the bottom cell 106 .

[0165] In some examples, the first transport layer may be one of an electron transport layer and a hole transport layer, and the second transport layer may be the other of the electron transport layer and the hole transport layer.

[0166] In some embodiments, the band gap width of the top cell 107 is wider than that of the bottom cell 106. Therefore, stacking the top cell 107 on the bottom cell 106 can enable the stacked cell to have a wider spectral response range, thereby maximizing the use of solar energy and improving the efficiency of the solar cell.

[0167] In some embodiments, the back-contact stacked cell may further include an intermediate connecting layer (not shown in the figure), which is connected between the bottom cell 106 and the top cell 107 .

[0168] In some cases, the intermediate connecting layer is typically a tunnel junction or a very thin metal or transparent electrode composite layer. Alternatively, the intermediate connecting layer can be a transparent conductive oxide, which has excellent optoelectronic properties, high photon transmittance and high conductivity, thereby maintaining good ohmic contact between the top cell 107 and the bottom cell 106.

[0169] In other cases, the back fine grid, back main grid, front fine grid and front main grid in the photovoltaic cell serving as the bottom cell 106 can also be used as an intermediate connection layer to achieve electrical connection with the top cell 107 .

[0170] Another embodiment of the present disclosure provides a photovoltaic assembly, comprising a plurality of photovoltaic cells as provided in the preceding embodiments, or a plurality of photovoltaic cells formed by the methods for manufacturing photovoltaic cells as provided in the preceding embodiments, or a plurality of connected laminated cells as provided in the preceding embodiments, the photovoltaic assembly being configured to convert received light energy into electrical energy. It should be noted that for portions identical or corresponding to the preceding embodiments, reference may be made to the corresponding descriptions of the preceding embodiments and will not be repeated below.

[0171] Combined with reference Figure 15 、 Figure 16 as well as Figures 1 to 13 The photovoltaic module includes: a cell string, which is formed by connecting multiple photovoltaic cells 40 provided by the aforementioned embodiments, or by connecting multiple photovoltaic cells 40 formed by the photovoltaic cell manufacturing method provided by the aforementioned embodiments, or by connecting multiple laminated cells provided by the aforementioned embodiments; an encapsulation film 41, which is used to cover the surface of the cell string; and a cover plate 42, which is used to cover the surface of the encapsulation film 41 facing away from the cell string.

[0172] in, Figure 15 A partial three-dimensional schematic diagram of a cell string in a photovoltaic module provided by yet another embodiment of the present disclosure; Figure 16 A partial cross-sectional schematic diagram of a photovoltaic assembly provided in yet another embodiment of the present disclosure.

[0173] In some embodiments, the photovoltaic cell 40 is electrically connected in a whole cell or multiple slices to form multiple cell strings, and the multiple cell strings are electrically connected in series and / or parallel. The photovoltaic cell 40 can be a whole cell or a sliced ​​cell. A sliced ​​cell refers to a cell formed by cutting a complete whole cell.

[0174] In some embodiments, in conjunction with reference Figure 15 and Figure 16 , multiple photovoltaic cells 40 can be electrically connected through conductive tapes 43. Figure 15 and Figure 16Only one positional relationship between the photovoltaic cells 40 is illustrated, i.e., the gridlines of the photovoltaic cells 40 having the same polarity are arranged in the same direction, or the gridlines of each photovoltaic cell 40 having the positive polarity are arranged toward the same side, so that the conductive ribbons 43 connect different sides of two adjacent photovoltaic cells 40. In other embodiments, the photovoltaic cells may also have electrodes of different polarities facing the same side, i.e., the electrodes of multiple adjacent photovoltaic cells may be arranged in the order of first polarity, second polarity, and first polarity, respectively, so that the conductive ribbons connect two adjacent photovoltaic cells on the same side.

[0175] In some embodiments, the encapsulation film 41 includes a first encapsulation layer and a second encapsulation layer, wherein the first encapsulation layer covers one of the front and back sides of the photovoltaic cell 40, and the second encapsulation layer covers the other of the front and back sides of the photovoltaic cell 40. Specifically, at least one of the first encapsulation layer or the second encapsulation layer can be an organic encapsulation film such as polyvinyl butyral (PVB) film, ethylene-vinyl acetate copolymer (EVA) film, polyethylene octene co-elastomer (POE) film, or polyethylene terephthalate (PET) film, or at least one of the first encapsulation layer or the second encapsulation layer can also be an EP film, EPE film, or PVP film. Among them, EP film refers to a co-extruded film composed of stacked EVA film and POE film, EPE film refers to a co-extruded film formed by stacking EVA film + POE film + EVA film in sequence, and PVP film refers to a co-extruded film formed by stacking POE film + EVA film + POE film. Co-extruded films can be prepared by sequentially extruding one or more raw materials onto another already manufactured film during the film processing process, or by bonding different types of already manufactured films together.

[0176] In some cases, there is a boundary line between the first encapsulation layer and the second encapsulation layer before lamination. After the lamination process, the photovoltaic module is formed and there is no longer the concept of the first encapsulation layer and the second encapsulation layer, that is, the first encapsulation layer and the second encapsulation layer have formed an integral encapsulation film 41.

[0177] In some embodiments, the cover plate 42 may be a light-transmitting cover plate such as a glass cover plate or a plastic cover plate. Specifically, the surface of the cover plate 42 facing the encapsulation film 41 may have a concave-convex surface or a velvet surface including multiple raised structures, thereby increasing the utilization of incident light. The cover plate 42 includes a first cover plate and a second cover plate. The first cover plate faces the first encapsulation layer, and the second cover plate faces the second encapsulation layer.

[0178] Those skilled in the art will appreciate that the above-described embodiments are specific examples for implementing the present disclosure, and in actual applications, various changes may be made to them in form and detail without departing from the spirit and scope of the embodiments of the present disclosure. Any person skilled in the art may make various changes and modifications without departing from the spirit and scope of the embodiments of the present disclosure. Therefore, the scope of protection of the embodiments of the present disclosure shall be based on the scope defined in the claims.

Claims

1. A photovoltaic cell, characterized in that: include: The battery substrate has a first surface and a second surface opposite to each other in a thickness direction; a plurality of grid lines located on the first surface and / or the second surface and arranged at intervals along a first direction, the grid lines comprising a contact structure electrically connected to the battery substrate and a connection layer, the contact structure comprising a plurality of contact portions sequentially arranged along a second direction, the connection layer being a long strip-shaped structure extending along the second direction, the first direction and the second direction being perpendicular to each other; In which, the connecting layer is in contact with and connected to multiple contact portions in the contact structure, the material of the contact portion is different from the material of the connecting layer, and the orthographic projections of the contact portion and the connecting layer on the battery substrate partially overlap; the contact portion includes a first contact portion and a second contact portion alternately arranged along the second direction, the connecting layer has a first side portion and a second side portion opposite to each other along the first direction, the first contact portion is in contact with at least the first side portion and the second contact portion is in contact with the second side portion, or the second contact portion is in contact with at least the second side portion and the first contact portion is in contact with the first side portion.

2. The photovoltaic cell according to claim 1, characterized in that In the same gate line, the first contact portion and the second contact portion are not directly opposite to each other along the second direction.

3. The photovoltaic cell according to claim 1, characterized in that In the same gate line, a partial area of ​​the first contact portion and a partial area of ​​the second contact portion are opposite to each other along the second direction.

4. The photovoltaic cell according to claim 3, characterized in that Along the second direction, a portion of the first contact portion facing the second contact portion is a first portion, and a width of a portion of the first contact portion other than the first portion in the first direction is less than or equal to 25 μm.

5. The photovoltaic cell according to any one of claims 1 to 4, characterized in that Along the thickness direction, the orthographic projection shape of the contact portion on the battery substrate is a circle, an ellipse, a triangle, a rectangle, a trapezoid or an N-gon, where N is a positive integer greater than 4.

6. The photovoltaic cell according to any one of claims 1 to 4, characterized in that Along the thickness direction, the orthographic projection of the contact portion on the battery substrate is circular or elliptical, and the first contact portion and the second contact portion adjacent to each other along the second direction are tangent to each other.

7. The photovoltaic cell according to any one of claims 1 to 4, characterized in that Along the thickness direction, the orthographic projection area of ​​the contact portion on the battery substrate is 100 μm 2 ~5000μm 2 .

8. The photovoltaic cell according to claim 1, characterized in that Along the first direction, the width of the connection layer is 10 μm to 70 μm.

9. The photovoltaic cell according to claim 1, characterized in that In the first contact portion and the second contact portion adjacent to each other along the second direction, the edge of the first contact portion closest to the second contact portion is a first edge, the edge of the second contact portion closest to the first contact portion is a second edge, and the distance between the first edge and the second edge is less than or equal to 200 μm.

10. The photovoltaic cell according to claim 1, characterized in that Along the thickness direction, the thickness of the contact portion is 1 μm to 10 μm; and / or the thickness of the connection layer is 4 μm to 20 μm.

11. The photovoltaic cell according to claim 1, characterized in that The gate line is one of a fine gate and a main gate, and the other of the fine gate and the main gate is a long strip structure extending along the first direction.

12. The photovoltaic cell according to claim 1, characterized in that The grid lines are fine grids, and the photovoltaic cell further comprises: a plurality of busbars located on at least one of the first surface and the second surface and arranged at intervals along the second direction, the busbars comprising a connection structure electrically connected to the battery substrate and an interconnection layer, the connection structure comprising a plurality of connection portions sequentially arranged along the first direction, and the interconnection layer being a long strip-shaped structure extending along the first direction; The interconnection layer is in contact with and connected to a plurality of the connection portions in the connection structure, and the connection portions include a first connection portion and a second connection portion alternately arranged along the second direction. The interconnection layer has a third side portion and a fourth side portion opposite to each other along the first direction. The first connection portion is in contact with and connected to at least the third side portion, and the second connection portion is in contact with and connected to at least the fourth side portion, and the material of the connection portion is different from the material of the interconnection layer.

13. The photovoltaic cell according to claim 1, characterized in that The material of the contact portion includes silver particles, and the material of the connection layer includes copper particles or silver-coated copper particles.

14. The photovoltaic cell according to claim 13, characterized in that: The diameter of the copper particles is 50 nm to 1500 nm; or the diameter of the silver-coated copper particles is 1 μm to 10 μm; or the proportion of silver in the silver-coated copper particles is 15% to 50%.

15. A method for manufacturing a photovoltaic cell, characterized in that: include: Providing a battery substrate, the battery substrate having a first surface and a second surface opposite to each other in a thickness direction; A plurality of gate lines are formed on the first surface and / or the second surface and arranged at intervals along a first direction, wherein the gate lines include a contact structure electrically connected to the battery substrate and a connection layer, the contact structure includes a plurality of contact portions arranged in sequence along a second direction, and the connection layer is a long strip structure extending along the second direction, wherein the first direction and the second direction are perpendicular to each other; In which, the connecting layer is in contact with and connected to multiple contact portions in the contact structure, the material of the contact portion is different from the material of the connecting layer, and the orthographic projections of the contact portion and the connecting layer on the battery substrate partially overlap; the contact portion includes a first contact portion and a second contact portion alternately arranged along the second direction, the connecting layer has a first side portion and a second side portion opposite to each other along the first direction, the first contact portion is in contact with at least the first side portion and the second contact portion is in contact with the second side portion, or the second contact portion is in contact with at least the second side portion and the first contact portion is in contact with the first side portion.

16. The method for manufacturing a photovoltaic cell according to claim 15, wherein: The grid lines are fine grids; the second surface has a first printing area and a second printing area that at least partially overlaps with the first printing area; The steps of forming the gate lines include: using a first screen printing process to print a first paste on the first printing area; sintering the first paste to form the contact structure corresponding to the first printing area; using a second screen printing process to print a second paste on the second surface; and curing the second paste to form the connection layer corresponding to the second printing area. The first slurry is a burn-through slurry, and the second slurry is a non-burn-through slurry; the process temperature of the sintering treatment is higher than the process temperature of the curing treatment.

17. The method for manufacturing a photovoltaic cell according to claim 16, wherein: The first paste is silver paste, and the second paste is copper paste or silver-coated copper paste.

18. The method for manufacturing a photovoltaic cell according to claim 17, wherein: The solid content of the silver paste is 75% to 92%.

19. The method for manufacturing a photovoltaic cell according to claim 16, wherein: The second side also has a third printed area; In the step of performing the first screen printing process, the first slurry is further printed on the third printing area, and in the step of performing the sintering process, a main grid corresponding to the third printing area is further formed; or, The second paste is further printed on the third printing area during the second screen printing process, and a main grid corresponding to the third printing area is further formed during the curing process.

20. The method for manufacturing a photovoltaic cell according to claim 19, wherein: The fine grid formed on the second surface is a back fine grid, and the main grid formed on the second surface is a back main grid; the first surface has a fourth printing area extending along the first direction, and a fifth printing area extending along the second direction; Before performing the sintering process, the method for manufacturing the photovoltaic cell further includes: A third screen printing process is adopted to print a third paste on the fourth printing area; in the step of performing the sintering treatment, the third paste is also subjected to the sintering treatment to form a front fine grid corresponding to the fourth printing area; a fourth screen printing process is adopted to print a fourth paste on the fifth printing area; in the step of performing the sintering treatment, the fourth paste is also subjected to the sintering treatment to form a front main grid corresponding to the fifth printing area.

21. A laminated battery, characterized in that: include: A bottom cell, wherein the bottom cell is the photovoltaic cell according to any one of claims 1 to 14, or is a photovoltaic cell formed by the method for manufacturing a plurality of photovoltaic cells according to any one of claims 15 to 20; A top cell is located on one side of the bottom cell.

22. A photovoltaic module, characterized in that: include: A cell string formed by connecting a plurality of photovoltaic cells according to any one of claims 1 to 14, or by connecting a plurality of photovoltaic cells formed by the method for manufacturing a photovoltaic cell according to any one of claims 15 to 20, or by connecting a plurality of laminated cells according to claim 21; A packaging film, used to cover the surface of the battery string; A cover plate is used to cover the surface of the packaging film facing away from the battery string.

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