Back contact cells and methods and apparatus for their manufacture, stacked cells, photovoltaic modules

Abstract

The present disclosure relates to the field of photovoltaics, and provides a back contact cell, a manufacturing method and device thereof, a laminated cell, and a photovoltaic module. The back contact cell comprises a cell substrate comprising first and second regions arranged alternately along a first direction and a third region between the first and second regions; first and second fine grids arranged alternately along a second direction; the first fine grid comprises a first portion located in the first region, a second portion located in the second region, and a third portion located in the third region; the second fine grid comprises a fourth portion located in the first region, a fifth portion located in the second region, and a sixth portion located in the third region; first and second bus electrodes arranged alternately along the first direction; the first bus electrode is located in the first region and connected to the first portion; the second bus electrode is located in the second region and connected to the fifth portion; and an insulating layer comprising at least one of silicon oxide or magnesium fluoride is located on the surface of the second portion and the fourth portion or on the surface of the third portion and the sixth portion, which at least helps to improve the structural stability of the back contact cell.

Description

Technical Field

[0001] This disclosure relates to the photovoltaic field, and in particular to a back contact battery and its manufacturing method and apparatus, a tandem battery, and a photovoltaic module. Background Technology

[0002] With the gradual depletion of fossil fuels, photovoltaic cells are becoming increasingly widely used as a new energy alternative. A photovoltaic cell is a device that converts solar energy into electrical energy. It utilizes the photovoltaic principle to generate charge carriers, which are then extracted using electrodes, thus facilitating the efficient use of electrical energy.

[0003] Current photovoltaic cells mainly include BC cells (Back Contact Cell), TOPCON cells (Tunnel Oxide Passivated Contact Cell), PERC cells (Passivated Emitter and Rear Cell), and heterojunction cells (Heterojunction with Intrinsic Thin-layer, abbreviated as HIT or HJT).

[0004] However, since the current-leading components in BC batteries are all located on the back, the structural stability of BC batteries remains poor. Summary of the Invention

[0005] This disclosure provides a back contact battery and its manufacturing method and apparatus, a tandem battery, and a photovoltaic module, which at least helps to improve the structural stability of the back contact battery.

[0006] This disclosure provides a back-contact battery, comprising: a battery substrate including a first region and a second region alternately arranged along a first direction, and a third region located between the first region and the second region; a first fine grid and a second fine grid disposed on the battery substrate and alternately arranged along a second direction, the second direction being a direction intersecting the first direction; wherein the first fine grid includes a first portion located in the first region, a second portion located in the second region, and a third portion located in the third region, and the second fine grid includes a fourth portion located in the first region, a fifth portion located in the second region, and a sixth portion located in the third region; a first bus electrode and a second bus electrode disposed on the battery substrate and alternately arranged along the first direction, the first bus electrode being located in the first region and connected to the first portion, and the second bus electrode being located in the second region and connected to the fifth portion; an insulating layer located on the surface of the second portion and the surface of the fourth portion, or on the surface of the third portion and the surface of the sixth portion; the material of the insulating layer includes at least one of silicon oxide or magnesium fluoride.

[0007] Optionally, the insulating layer includes a first insulating layer located in the first region and a second insulating layer located in the second region; the first insulating layer includes two first insulating portions located on opposite sides of the first bus electrode, the first insulating portions being at least located on the surface of the fourth portion; the second insulating layer includes two second insulating portions located on opposite sides of the second bus electrode, the second insulating portions being at least located on the surface of the second portion.

[0008] Optionally, the first insulating portion includes a plurality of first insulating blocks arranged along the second direction, the first insulating blocks being located on the surface of the fourth portion; the second insulating portion includes a plurality of second insulating blocks arranged along the second direction, the second insulating blocks being located on the surface of the second portion.

[0009] Optionally, the first insulating layer extends along the second direction, and along the second direction, the first insulating layer is also located on the surface of the portion of the first part corresponding to the fourth part; the second insulating layer extends along the second direction, and along the second direction, the second insulating layer is also located on the surface of the portion of the fifth part directly opposite the second part.

[0010] Optionally, the insulating layer includes a plurality of first insulating strips located in the first region and arranged along the second direction, and a plurality of second insulating strips located in the second region and arranged along the second direction; wherein, the first insulating strip is disposed between the battery substrate and the first bus electrode, and the second insulating strip is disposed between the battery substrate and the second bus electrode.

[0011] Optionally, a first insulating strip is provided between the fourth part and the first bus electrode, and a second insulating strip is provided between the second part and the second bus electrode.

[0012] Optionally, the back contact battery further includes a reflective layer; wherein the reflective layer is located on the side of the insulating layer away from the battery substrate; or, the reflective layer is located on the surface formed by the insulating layer and the first bus electrode, and / or, on the surface formed by the insulating layer and the second bus electrode.

[0013] Optionally, the insulating layer is located on the surface of the third part and the surface of the sixth part; the back contact battery further includes a reflective layer located on the side of the insulating layer away from the battery substrate.

[0014] Optionally, along the first direction, the width of the first region or the width of the second region is 0.2cm to 1cm; and / or, the width of the third region is 0.5cm to 1.2cm.

[0015] Optionally, the thickness of the insulating layer is less than the thickness of the reflective layer.

[0016] Optionally, the thickness of the insulating layer is 20nm~50nm; and / or, the thickness of the reflective layer is 200nm~300nm.

[0017] This disclosure also provides a method for manufacturing a back-contact battery, comprising: obtaining a battery substrate, the battery substrate including a first region and a second region alternately arranged along a first direction, and a third region located between the first region and the second region; forming a first fine grid and a second fine grid alternately arranged along a second direction on the battery substrate, the second direction being a direction intersecting the first direction; wherein the first fine grid includes a first portion located in the first region, a second portion located in the second region, and a third portion located in the third region, and the second fine grid includes a fourth portion located in the first region, a fifth portion located in the second region, and a sixth portion located in the third region; forming a first bus electrode, a second bus electrode, and an insulating layer alternately arranged along the first direction on the battery substrate, the first bus electrode being located in the first region and connected to the first portion, and the second bus electrode being located in the second region and connected to the fifth portion; the insulating layer being made of at least one of silicon oxide or magnesium fluoride; the insulating layer being located on the surface of the second portion and the surface of the fourth portion, or on the surface of the third portion and the surface of the sixth portion.

[0018] Optionally, after forming the first fine gate and the second fine gate, and before forming the first bus electrode and the second bus electrode, the insulating layer is formed on the surface of the second part and the surface of the fourth part.

[0019] Optionally, after forming the first bus electrode and the second bus electrode, and before forming the insulating layer, the method further includes: forming a mask on the first region and the second region; the step of forming the insulating layer includes: forming an initial insulating layer on the surface jointly formed by the first fine gate, the second fine gate and the mask; removing the mask, and the remaining initial insulating layer located on the third region is the insulating layer.

[0020] Optionally, the method for manufacturing the back contact battery further includes forming a reflective layer on the side of the insulating layer away from the battery substrate.

[0021] This disclosure also provides a manufacturing apparatus for a back contact battery, comprising: an acquisition module for acquiring a battery substrate, the battery substrate including a first region and a second region alternately arranged along a first direction, and a third region located between the first region and the second region; a first manufacturing module for forming a first fine grid and a second fine grid alternately arranged along a second direction on the battery substrate, the second direction being a direction intersecting the first direction; wherein the first fine grid includes a first portion located in the first region, a second portion located in the second region, and a third portion located in the third region, and the second fine grid includes a fourth portion located in the first region, a fifth portion located in the second region, and a sixth portion located in the third region; a second manufacturing module for forming a first bus electrode, a second bus electrode, and an insulating layer alternately arranged along the first direction on the battery substrate, the first bus electrode being located in the first region and connected to the first portion, the second bus electrode being located in the second region and connected to the fifth portion; the insulating layer being made of at least one of silicon oxide or magnesium fluoride; the insulating layer being located on the surface of the second portion and the surface of the fourth portion, or on the surface of the third portion and the surface of the sixth portion.

[0022] This disclosure also provides a tandem battery, comprising: a crystalline silicon bottom battery, which is a back contact battery as described in any of the preceding claims, or a back contact battery formed by a manufacturing method of a back contact battery as described in any of the preceding claims, or a back contact battery formed by a manufacturing apparatus of a back contact battery as described in any of the preceding claims; and a perovskite top battery, which is located on one side of the crystalline silicon bottom battery.

[0023] This disclosure also provides a photovoltaic module, comprising: a battery string, formed by connecting a plurality of back-contact batteries as described in any of the preceding claims, or formed by connecting a plurality of back-contact batteries formed by a manufacturing method of a back-contact battery as described in any of the preceding claims, or formed by connecting a plurality of back-contact batteries formed by a manufacturing apparatus of a back-contact battery as described in any of the preceding claims, or formed by connecting a plurality of stacked batteries as described in the preceding claims; an encapsulation layer for covering the surface of the battery string; and a cover plate for covering the surface of the encapsulation layer opposite to the battery string.

[0024] The technical solution provided in this disclosure has at least the following advantages: Based on increasing the distribution density of the first and second fine grids in the back contact battery, in some cases, the insulating layer located on the surface of the fourth part can prevent the first bus electrode from being electrically connected to the second fine grid, and the insulating layer located on the surface of the second part can prevent the second bus electrode from being electrically connected to the first fine grid; or, in some cases, the insulating layer located on the surfaces of the third and sixth parts can prevent the first bus electrode from being electrically connected to the second bus electrode, thereby avoiding internal short circuit problems in the back contact battery. Moreover, compared with using insulating adhesive to avoid internal short circuit problems in the back contact battery, on the one hand, the insulating layer, which includes at least one of silicon oxide or magnesium fluoride, has a lower coefficient of thermal expansion, thereby effectively preventing the back contact battery from warping due to the insulating layer when the back contact battery undergoes high temperature and cooling, thus improving the structural stability of the back contact battery; on the other hand, the insulating layer, which includes at least one of silicon oxide or magnesium fluoride, has higher density, which can provide better protection for the back contact battery and improve the back contact battery's resistance to PID (Potential Induced Degradation). Attached Figure Description

[0025] One or more embodiments are illustrated by way of example with corresponding pictures in the accompanying drawings. These illustrations do not constitute a limitation on the embodiments. Unless otherwise stated, the pictures in the accompanying drawings do not constitute a limitation on scale. In order to more clearly illustrate the technical solutions in the embodiments of this disclosure or the conventional technology, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this disclosure. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0026] Figure 1 This is a partial top view of a first embodiment of a back contact battery provided in this disclosure. Figure 2 for Figure 1 The diagram shows a top view of the first type of back contact battery with an added insulating layer. Figure 3 for Figure 1 The diagram shows a second top view of a battery with an added insulating layer in the back contact cell. Figure 4 for Figure 3 The diagram shows a first cross-sectional structure of the back contact battery along the first cross-sectional direction AA1. Figure 5 for Figure 3 The diagram shows a second cross-sectional structure of the back contact battery along the first cross-sectional direction AA1. Figure 6This is a partial top view of a second type of back contact battery provided in an embodiment of the present disclosure; Figure 7 This is a partial top view of a third type of back contact battery provided in an embodiment of the present disclosure. Figure 8 This is a partial top view of a fourth type of back contact battery provided in an embodiment of the present disclosure. Figure 9 This is a partial top view of a fifth type of back contact battery provided in an embodiment of the present disclosure; Figure 10 for Figure 9 The diagram shows a top view of a back-contact battery with an added insulating layer. Figure 11 for Figure 8 The diagram shows a first cross-sectional structure of the back contact battery along the second cross-section direction BB1. Figure 12 for Figure 8 The diagram shows a second cross-sectional structure of the back contact battery along the second cross-sectional direction BB1. Figure 13 for Figure 3 The diagram shows a cross-sectional structure of the back contact battery along the third section direction CC1. Figure 14 A process flow diagram of a method for manufacturing a back contact battery according to an embodiment of this disclosure; Figure 15 A schematic diagram of a functional module of a manufacturing apparatus for a back contact battery provided in an embodiment of this disclosure; Figure 16 This is a partial cross-sectional structural diagram of a stacked battery provided in an embodiment of the present disclosure. Figure 17 This is a partial three-dimensional schematic diagram of a cell string in a photovoltaic module provided in an embodiment of the present disclosure; Figure 18 This is a partial cross-sectional schematic diagram of a photovoltaic module provided in an embodiment of the present disclosure.

[0027] Explanation of reference numerals in the attached figures: 100, Battery substrate; 110, First region; 120, Second region; 130, Third region; 140, Substrate; 1401, Fourth region; 1402, Fifth region; 1403, Spacer region; 150, First passivation layer; 160, First doped conductive portion; 170, Second passivation layer; 180, Second doped conductive portion; 190, Transparent conductive layer; 101, First fine grid; 111, First part; 121, Second part; 131, Third part; 102, Second fine grid; 112, Fourth part; 122, Fifth part; 132, Sixth part; 103, First bus electrode; 113, First main grid; 123, First pad; 133, First... 104. Solder ribbon; 114. Second busbar; 124. Second pad; 134. Second solder ribbon; 105. Insulating layer; 115. First insulating layer; 125. Second insulating layer; 135. First insulating part; 1351. First insulating block; 145. Second insulating part; 1451. Second insulating block; 155. First insulating strip; 165. Second insulating strip; 175. Initial insulating layer; 106. Reflective layer; 109. Acquisition module; 119. First manufacturing module; 129. Second manufacturing module; 139. Crystalline silicon bottom cell; 149. Perovskite top cell; 40. Back contact cell; 41. Encapsulation layer; 42. Cover plate. Detailed Implementation

[0028] As can be seen from the background technology, there is a need to study how to improve the structural stability of back contact batteries.

[0029] This disclosure provides a back contact battery and its manufacturing method and apparatus, a tandem battery, and a photovoltaic module. In the back contact battery, based on increasing the distribution density of the first and second fine grids, in some cases, the surface of the insulating layer located in the fourth part can prevent the first bus electrode from being electrically connected to the second fine grid, and the surface of the insulating layer located in the second part can prevent the second bus electrode from being electrically connected to the first fine grid; or, in some cases, the surfaces of the insulating layer located in the third and sixth parts can prevent the first bus electrode from being electrically connected to the second bus electrode, thereby avoiding internal short circuit problems in the back contact battery. Moreover, compared with using insulating adhesive to avoid internal short circuit problems in the back contact battery, on the one hand, the insulating layer made of at least one of silicon oxide or magnesium fluoride has a lower coefficient of thermal expansion, thereby effectively avoiding the problem of back contact battery warping caused by the insulating layer when the back contact battery undergoes high temperature and cooling, thus improving the structural stability of the back contact battery; on the other hand, the insulating layer made of at least one of silicon oxide or magnesium fluoride has higher density, which can provide better protection for the back contact battery and improve the anti-PID performance of the back contact battery.

[0030] In the description of the embodiments of this disclosure, technical terms such as "first" and "second" are used only to distinguish different objects and should not be construed as indicating or implying relative importance or implicitly specifying the number, specific order, or primary or secondary relationship of the indicated technical features. In the description of the embodiments of this disclosure, "multiple" means two or more (including two), unless otherwise explicitly defined. Similarly, "multiple sets" refers to two or more sets (including two sets), and "multiple pieces" refers to two or more pieces (including two pieces).

[0031] In this document, the term "embodiment" means that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of this disclosure. The appearance of this phrase in various places throughout the specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment mutually exclusive with other embodiments. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments.

[0032] In the description of the embodiments of this disclosure, the term "and / or" is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent three cases: A exists, A and B exist simultaneously, and B exists. Additionally, the character " / " in this document generally indicates that the preceding and following related objects have an "or" relationship.

[0033] In the description of the embodiments of this disclosure, the technical terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential," etc., indicating orientation or positional relationships, are based on the orientation or positional relationships shown in the accompanying drawings and are only for the convenience of describing the embodiments of this disclosure and simplifying the description. They do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation on the embodiments of this disclosure. For example, if the device or element in the illustration is inverted, then the element described as "below," "under," "below," or "bottom" of other elements or features will be oriented "above" or "top" of said other elements or features. Therefore, the term "below" may, depending on the context in which the term is used, encompass both above and below orientations, which will be obvious to those skilled in the art. Materials may be oriented in other ways (e.g., rotated 90 degrees, inverted, flipped), and the spatial relative descriptive terms used herein may be interpreted accordingly.

[0034] In the description of the embodiments of this disclosure, unless otherwise expressly specified and limited, technical terms such as "installation," "connection," "joining," and "fixing" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in the embodiments of this disclosure according to the specific circumstances.

[0035] In the description of the embodiments disclosed herein, electrical connection between one component and another means that both components are made of conductive materials, and the two components are in direct contact and connected or connected via other conductive materials, so that current flows between the two components when the device is generating electricity. Electrical contact between one component and another means that the two components are not only in contact, but also that current flows between them when the device is generating electricity because both components are made of conductive materials.

[0036] In the description of embodiments of this disclosure, the terms "about," "approximately," "roughly," or "about" for a numerical value referring to a specific parameter include the numerical value, and those skilled in the art will understand that the deviation from the numerical value is within acceptable tolerances of the specific parameter. For example, "about" or "about" for a numerical value may include additional numerical values ​​that are in the range of 90.0% to 110.0% of the numerical value, such as in the range of 95.0% to 105.0%, 97.5% to 102.5%, 99.0% to 101.0%, 99.5% to 100.5%, or 99.9% to 100.1%.

[0037] In the accompanying drawings corresponding to the embodiments of this disclosure, the thickness and / or area of ​​layers, films, panels, regions, etc., are enlarged for better understanding and ease of description. Throughout the specification, the same reference numerals denote the same elements. Furthermore, when describing a component as being "generally" formed on another component, it means that the component is not formed on the entire surface (or front surface) of the other component, nor on a portion of the edge of the entire surface.

[0038] In the description of embodiments of this disclosure, when a component "includes" another component, other components are not excluded unless otherwise stated, and may be further included. 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 there may be an intermediate component between the two components. Conversely, when a component is described as being on the surface of another component, or a component is "directly" on another component, or another component is formed or disposed on the surface of a component, it indicates that there is no intermediate component between the two components. For simplicity and clarity, various components may be drawn at any scale. In the drawings, some components may be omitted for simplicity.

[0039] The terminology used in the description of the various embodiments herein is for the purpose of describing particular embodiments only and is not intended to be limiting. As used in the description of the various embodiments and the appended claims, the term "the component" is also intended to include the plural form unless the context clearly indicates otherwise.

[0040] The “components” mentioned above can refer to layers, films, regions, parts, structures, etc.

[0041] The embodiments of this disclosure will now be described in detail with reference to the accompanying drawings. However, those skilled in the art will understand that many technical details have been provided in the embodiments of this disclosure to facilitate a better understanding of the embodiments. However, the technical solutions claimed in the embodiments of this disclosure can be implemented even without these technical details and various variations and modifications based on the following embodiments.

[0042] This disclosure provides an embodiment of a back contact battery, which will be described in detail below with reference to the accompanying drawings.

[0043] refer to Figures 1 to 3The back contact battery includes: a battery substrate 100, comprising a first region 110 and a second region 120 arranged alternately along a first direction X, and a third region 130 located between the first region 110 and the second region 120; a first finger electrode 101 and a second finger electrode 102 disposed on the battery substrate 100 and arranged alternately along a second direction Y, wherein the second direction Y is the direction intersecting the first direction X; wherein the first finger electrode 101 includes a first part 111 located in the first region 110, a second part 121 located in the second region 120, and a third part 131 located in the third region 130, and the second finger electrode 102 includes a fourth part 112 located in the first region 110, a fifth part 122 located in the second region 120, and a sixth part 132 located in the third region 130; and a first bus electrode 103 and a second bus electrode 104 disposed on the battery substrate 100 and arranged alternately along the first direction X. The first bus electrode 103 is located in the first region 110 and connected to the first part 111, the second bus electrode 104 is located in the second region 120 and connected to the fifth part 122; the insulating layer 105 is made of at least one of silicon oxide or magnesium fluoride.

[0044] Among them, in conjunction with reference Figure 1 and Figure 2 The insulating layer 105 is located on the surface of the second part 121 and the surface of the fourth part 112; or, in conjunction with reference to... Figure 1 and Figure 3 The insulating layer 105 is located on the surface of the third part 131 and the surface of the sixth part 132.

[0045] Figure 1 This is a partial top view of a first type of back contact battery provided in an embodiment of the present disclosure; Figure 2 for Figure 1 The diagram shows a top view of the first type of back contact battery with an added insulating layer. Figure 3 for Figure 1 The diagram shows a second top view of the battery with an added insulating layer in the back contact section. Furthermore, Figure 1 The first part 111, the second part 121 and the third part 131 of the first fine grid 101 are clearly divided by dashed lines, and the fourth part 112, the fifth part 122 and the sixth part 132 of the second fine grid 102 are also clearly divided by dashed lines.

[0046] The first fine grid 101 and the second fine grid 102 are used to collect different types of photogenerated carriers generated in the back contact battery, respectively, and the first bus electrode 103 and the second bus electrode 104 are used to collect different types of carriers, respectively. In other words, one of the first bus electrode 103 and the second bus electrode 104 can be regarded as the positive electrode of the back contact battery, and the other can be regarded as the negative electrode of the back contact battery. Therefore, in order to avoid the internal short circuit problem of the back contact battery, it is necessary to avoid electrical connection between the first bus electrode 103 and the second bus electrode 104, avoid electrical connection between the first bus electrode 103 and the second fine grid 102, and avoid electrical connection between the second bus electrode 104 and the first fine grid 101.

[0047] The electrical connection between the two components actually refers to the fact that both are made of conductive materials and are directly connected or connected via other conductive materials. Therefore, when the back contact battery is generating electricity, there is an electrical connection between them. Consequently, when the back contact battery is generating electricity, it is necessary to avoid an electrical connection between the first bus electrode 103 and the second bus electrode 104 or the second fine grid 102, and it is also necessary to avoid an electrical connection between the second bus electrode 104 and the first fine grid 101.

[0048] However, in order to increase the distribution density of the first fine grid 101 and the second fine grid 102 in the back contact battery, the first fine grid 101 usually has a portion very close to the second bus electrode 104, that is, the first fine grid 101 includes a second part 121 located in the second region 120, which is the same as the second bus electrode 104; the second fine grid 102 usually has a portion very close to the first bus electrode 103, that is, the second fine grid 102 includes a fourth part 112 located in the first region 110, which is the same as the first bus electrode 103.

[0049] Therefore, in some cases, in conjunction with references Figure 1 and Figure 2On the one hand, when the first bus electrode 103 is designed to be located in the first region 110 and connected to the first part 111, the surface of the fourth part 112 in the second fine gate 102, which is also located in the first region 110, is also designed to have an insulating layer 105. In this way, when the first bus electrode 103 collects the current in the first fine gate 101, the insulating layer 105 on the surface of the fourth part 112 can be used to prevent the first bus electrode 103 from being electrically connected to the second fine gate 102. On the other hand, when the second bus electrode 104 is designed to be located in the second region 120 and connected to the fifth part 122, the surface of the second part 121 in the first fine gate 101, which is also located in the second region 120, is also designed to have an insulating layer 105. In this way, when the second bus electrode 104 collects the current in the second fine gate 102, the insulating layer 105 on the surface of the second part 121 can be used to prevent the second bus electrode 104 from being electrically connected to the first fine gate 101. Moreover, compared to using insulating adhesive to avoid internal short circuits in the back contact battery, the insulating layer 105, which is made of at least one of silicon oxide or magnesium fluoride, has a lower coefficient of thermal expansion. This effectively prevents the back contact battery from warping due to the insulating layer 105 when the back contact battery is subjected to high temperature and cooling, thereby improving the structural stability of the back contact battery.

[0050] Alternatively, in some cases, in conjunction with references Figure 1 and Figure 3 When the first bus electrode 103 is located in the first region 110 and the second bus electrode 104 is located in the second region 120, an insulating layer 105 is also designed to be located between the first bus electrode 103 and the second bus electrode 104. For example, the insulating layer 105 is designed to be located on the surface of the third part 131 and the surface of the sixth part 132. The insulating layer 105 can be used to avoid electrical connection between the first bus electrode 103 and the second bus electrode 104. Moreover, compared with using insulating glue to avoid internal short circuit problems of the back contact battery, the insulating layer 105, which is made of at least one of silicon oxide or magnesium fluoride, can effectively avoid the problem of back contact battery warping caused by the insulating layer 105.

[0051] Furthermore, compared to the insulating layer 105, which is made of at least one of silicon dioxide or magnesium fluoride, the insulating adhesive typically comprises epoxy resin, acrylate, or silicone insulating adhesive. Therefore, the insulating layer 105 can effectively reduce the risk of back contact battery warping, and the higher density of the insulating layer 105 provides better protection for the back contact battery, improving its anti-PID performance.

[0052] The connection between the first bus electrode 103 and the first part 111 means that the first bus electrode 103 is directly connected to the first part 111 or is connected through other conductive materials; the connection between the second bus electrode 104 and the fifth part 122 means that the second bus electrode 104 is directly connected to the fifth part 122 or is connected through other conductive materials.

[0053] The following will provide a more detailed example of a back contact battery provided in an embodiment of the present disclosure, with reference to the accompanying drawings.

[0054] In some embodiments, reference Figure 1 The battery substrate 100 can refer to a pre-fabricated component. For example, the battery substrate 100 can be composed of a crystalline silicon substrate and various functional thin film layers deposited on the surface of the crystalline silicon substrate. In some embodiments, the functional thin film layers grown on the crystalline silicon substrate may include a passivation layer and / or an anti-reflection layer; in other embodiments, the functional thin film layers on the crystalline silicon substrate may also be additionally added doped silicon layers. In other words, the battery substrate 100 is not a bare silicon wafer; the battery substrate 100 can be equipped with various functional thin film layers according to actual process requirements.

[0055] In some cases, refer to Figure 4 or Figure 5 Battery substrate 100 (reference) Figure 1 The device may include: a substrate 140, which includes a fourth region 1401 and a fifth region 1402 arranged alternately along a second direction Y; a first passivation contact portion located at least in the fourth region 1401; and a second passivation contact portion located at least in the fifth region 1402. The first passivation contact portion may include at least: a first passivation layer 150 located at least in the fourth region 1401; and a first doped conductive portion 160 located on the side of the first passivation layer 150 away from the substrate 140. The second passivation contact portion may include at least: a second passivation layer 170 located at least in the fifth region 1402; and a second doped conductive portion 180 located on the side of the second passivation layer 170 away from the substrate 140.

[0056] Figure 4 for Figure 3 The diagram shows a first cross-sectional structure of the back contact battery along the first cross-sectional direction AA1. Figure 5 for Figure 3 The diagram shows a second cross-sectional structure of the back contact battery along the first cross-sectional direction AA1.

[0057] In some examples, the back contact cell can be an HBC cell (Heterojunction Back Contact Cell), and the materials of the first passivation layer 150 and the second passivation layer 170 can include at least one of amorphous silicon, microcrystalline silicon, or nanocrystalline silicon.

[0058] In some examples, the back contact cell can be a TBC cell (TOPCon Back Contact Cell, tunneled oxide passivated back contact cell), and the materials of the first passivation layer 150 and the second passivation layer 170 can both include at least one of silicon oxide, aluminum oxide, silicon nitride, silicon oxynitride, titanium oxide, hafnium oxide, zirconium oxide or silicon carbide.

[0059] In some examples, the back contact cell can be an HTBC cell (Heterojunction Tunnel Oxide Passivated Back Contact Cell). The material of one of the first passivation layer 150 and the second passivation layer 170 can include at least one of amorphous silicon, microcrystalline silicon, or nanocrystalline silicon. The material of the other of the first passivation layer 150 and the second passivation layer 170 can include at least one of silicon oxide, aluminum oxide, silicon nitride, silicon oxynitride, titanium oxide, hafnium oxide, zirconium oxide, or silicon carbide.

[0060] In some examples, the back contact cell can be an HPBC cell (Hybrid Passivated Back Contact Cell), and the material of one of the first passivation layer 150 and the second passivation layer 170 can include at least one of silicon oxide, aluminum oxide, silicon nitride, silicon oxynitride, titanium oxide, hafnium oxide, zirconium oxide, or silicon carbide, and the other of the first passivation layer 150 and the second passivation layer 170 can be an emitter structure.

[0061] In the above example, the material of the first doped conductive portion 160 and the material of the second doped conductive portion 180 may include a single-crystal, polycrystalline, amorphous, or microcrystalline silicon material layer. Based on this, the crystalline state of the first doped conductive portion 160 and the crystalline state of the second doped conductive portion 180 may include at least one of microcrystalline, nanocrystalline, microcrystalline, or a mixture of nanocrystalline and microcrystalline.

[0062] In the above example, the first doped conductive portion 160 is doped with one of a P-type dopant element and an N-type dopant element, and the second doped conductive portion 180 is doped with the other of a P-type dopant element and an N-type dopant element.

[0063] In some cases, refer to Figure 4 The back contact battery may further include: a transparent conductive layer 190, with a gap between the transparent conductive layer 190 located in the fourth region 1401 and the transparent conductive layer 190 located in the fifth region 1402; a first fine grid 101 located on the side of the transparent conductive layer 190 away from the first doped conductive portion 160, and a second fine grid 102 located on the side of the transparent conductive layer 190 away from the second doped conductive portion 180.

[0064] The material of the transparent conductive layer 190 may include at least one of indium oxide, tin-doped indium oxide, tungsten-doped indium oxide, titanium-doped indium oxide, cerium-doped indium oxide, molybdenum-doped indium oxide, hydrogen-doped indium oxide, zinc-doped indium oxide, zinc oxide, aluminum-doped zinc oxide, gallium-doped zinc oxide, tin oxide, or fluorine-doped tin oxide.

[0065] In some cases, refer to Figure 5 There can also be a gap 1403 between the fourth zone 1401 and the fifth zone 1402. In practical applications, there may also be no gap between the fourth zone and the fifth zone.

[0066] In some embodiments, reference Figure 1 Along the first direction X, the first region 110 will not be located at the edge of the back contact battery to avoid the first bus electrode 103 being too close to the edge of the back contact battery. Therefore, a third region 130 can also be designed on the side of the first region 110 that is close to the edge of the back contact battery. In other words, the first region 110 can have a third region 130 on each of its opposite sides along the first direction X.

[0067] In some embodiments, reference Figure 1 Along the first direction X, the second region 120 will not be located at the edge of the back contact battery to avoid the second bus electrode 104 being too close to the edge of the back contact battery. Therefore, a third region 130 can also be designed on the side of the second region 120 that is close to the edge of the back contact battery. In other words, the two opposite sides of the second region 120 along the first direction X can each have a third region 130.

[0068] To facilitate the description of the relative positional relationship between the insulating layer 105 and the first fine grid 101 and the second fine grid 102, the battery substrate 100 is divided into a first region 110, a second region 120 and a third region 130. Based on the division of the first region 110, the second region 121 and the third region 130, the first fine grid 101 is divided into a first part 111, a second part 121 and a third part 131, and the second fine grid 102 is divided into a fourth part 112, a fifth part 122 and a sixth part 132.

[0069] Based on this, the first region 110 can be regarded as the area on the surface of the battery substrate 100 where the first busbar 103, the portion of the first fine grid 101 near the first busbar 103 (i.e., the first part 111), and the portion of the second fine grid 102 near the first busbar 103 (i.e., the fourth part 112) are placed; the second region 120 can be regarded as the area on the surface of the battery substrate 100 where the second busbar 104, the portion of the first fine grid 101 near the second busbar 104 (i.e., the second part 121), and the portion of the second fine grid 102 near the second busbar 104 (i.e., the fifth part 122) are placed.

[0070] In some embodiments, reference Figure 1 The back contact battery is a BC battery with a main grid. The first bus electrode 103 may include at least a first main grid 113, which extends along the second direction Y and is connected to a plurality of first parts 111. The second bus electrode 104 may include at least a second main grid 114, which extends along the second direction Y and is connected to a plurality of fifth parts 122.

[0071] In some cases, refer to Figure 6 , Figure 6 This is a partial top view of a second back-contact battery structure provided in an embodiment of the present disclosure. In addition to the first main grid 113, the first bus electrode 103 may also include at least one first pad 123 located on the side of the first main grid 113 away from the battery substrate 100. The first pad 123 is used to realize the connection between the first main grid 113 and the first solder strip (…). Figure 6 Electrical connections (not shown in the diagram), the first solder strip is used to achieve electrical connections between two adjacent back contact batteries.

[0072] In addition to the second main gate 114, the second bus electrode 104 may also include at least one second pad 124 located on the side of the second main gate 114 away from the battery substrate 100. The second pad 124 is used to implement the second main gate 114 and the second solder strip. Figure 6 Electrical connection (not shown), the second solder strip is used to realize the electrical connection between two adjacent back contact batteries.

[0073] In some embodiments, reference Figure 7 , Figure 7 This is a partial top view of a third type of back contact battery provided in an embodiment of the present disclosure. The back contact battery is a BC battery without a main grid. The first bus electrode 103 can be a first solder strip 133, which extends along the second direction Y and is connected to a plurality of first parts 111. The second bus electrode 104 can be a second solder strip 134, which extends along the second direction Y and is connected to a plurality of fifth parts 122.

[0074] In some cases, continue to refer to Figure 7 In addition to the first solder strip 133, the first bus electrode 103 may also include at least one first pad 123 located between the first solder strip 133 and the first part 111. The first pad 123 is used to realize the electrical connection between the first part 111 and the first solder strip 133, and the first solder strip 133 is used to realize the electrical connection between two adjacent back contact batteries.

[0075] In addition to the second solder strip 134, the second bus electrode 104 may also include at least one second solder pad 124 located between the second solder strip 134 and the fifth part 122. The second solder pad 124 is used to realize the electrical connection between the fifth part 122 and the second solder strip 134, and the second solder strip 134 is used to realize the electrical connection between two adjacent back contact batteries.

[0076] To clearly illustrate the first busbar electrode 103 and the second busbar electrode 104, when the back contact cell is a BC cell without a traditional main grid, the portion of the first solder ribbon 133 can be considered as a sub-component of the first busbar electrode 103 in the back contact cell, and the portion of the second solder ribbon 134 can be considered as a sub-component of the second busbar electrode 104 in the back contact cell. In practical applications, the first solder ribbon and the second solder ribbon can also be considered as components at the photovoltaic module end that include multiple back contact cells. In this case, the first busbar electrode at the back contact cell end can be considered as including multiple first pads, and the second busbar electrode at the back contact cell end can be considered as including multiple second pads.

[0077] The following combination Figures 6 to 8 A detailed example illustrating the arrangement of the insulating layer 105 is provided. Among other things, Figure 8 This is a partial top view of a fourth type of back-contact battery provided in an embodiment of the present disclosure.

[0078] In some embodiments, in conjunction with reference Figure 6 and Figure 7 or in conjunction with references Figure 6 and Figure 8 The insulating layer 105 may include a first insulating layer 115 located in the first region 110 and a second insulating layer 125 located in the second region 120; the first insulating layer 115 may include two first insulating portions 135 located on opposite sides of the first bus electrode 103, and the first insulating portions 135 are located at least on the surface of the fourth portion 112; the second insulating layer 125 may include two second insulating portions 145 located on opposite sides of the second bus electrode 104, and the second insulating portions 145 are located at least on the surface of the second portion 121.

[0079] The first insulating portion 135 prevents the portion of the second fine gate 102 closest to the first bus electrode 103 (i.e., the fourth portion 112) from being electrically connected to the first bus electrode 103, and a single first bus electrode 103 corresponds to two first insulating portions 135; the second insulating portion 145 prevents the portion of the first fine gate 101 closest to the second bus electrode 104 (i.e., the second portion 121) from being electrically connected to the second bus electrode 104, and a single second bus electrode 104 corresponds to two second insulating portions 145.

[0080] refer to Figure 6 In the second fine grid 102, the fourth portion 112 and the first bus electrode 103 are spaced apart along the first direction X. In other words, the orthographic projections of the second fine grid 102 and the first bus electrode 103 on the battery substrate 100 do not intersect. Furthermore, the first insulating portion 135 is located in the gap between the fourth portion 112 and the first bus electrode 103, and the first insulating portion 135 is not located on the surface of the first bus electrode 103.

[0081] In the first fine grid 101, the second portion 121 and the second bus electrode 104 are spaced apart along the first direction X. In other words, the orthographic projections of the first fine grid 101 and the second bus electrode 104 on the battery substrate 100 do not intersect. Furthermore, the second insulating portion 145 is located in the gap between the second portion 121 and the second bus electrode 104, and the second insulating portion 145 is not located on the surface of the second bus electrode 104.

[0082] The specific construction of the first insulating part 135 and the second insulating part 145 will be described in detail below.

[0083] In some cases, refer to Figure 6 and Figure 7 The first insulating portion 135 may include a plurality of first insulating pads 1351 arranged along the second direction Y, with the first insulating pads 1351 located on the surface of the fourth portion 112; the second insulating portion 145 includes a plurality of second insulating pads 1451 arranged along the second direction Y, with the second insulating pads 1451 located on the surface of the second portion 121. This approach helps to minimize the projected area (i.e., coverage area) of the insulating layer 105 on the battery substrate 100 while avoiding electrical connection between the first fine grid 101 and the second bus electrode 104, and also avoiding electrical connection between the second fine grid 102 and the first bus electrode 103, thereby reducing the amount of insulating layer 105 used and thus lowering the manufacturing cost of the back contact battery.

[0084] Figure 7 The example only shows a single first insulating block 1351 located on the surface of a single fourth part 112. In actual applications, a single first insulating block can also be located on the surfaces of multiple adjacent fourth parts, such as two or three adjacent fourth parts. Figure 7 The example shown is based on a single second insulating block 1451 located on the surface of a single second part 121. In actual applications, a single second insulating block may also be located on the surfaces of multiple adjacent second parts, such as two or three adjacent second parts.

[0085] In some cases, refer to Figure 6 and Figure 8The first insulating layer 115 can extend along the second direction Y and be upward along the second direction Y. The first insulating layer 115 can also be located on the surface of the portion of the first part 111 corresponding to the fourth part 112. The second insulating layer 125 can extend along the second direction Y and be upward along the second direction Y. The second insulating layer 125 can also be located on the surface of the portion of the fifth part 122 directly opposite to the second part 121. Figure 8 Can be regarded as Figure 6 The diagram shows a top view of a battery with an added insulating layer in the back contact section.

[0086] Thus, the portions of the first fine gates 101 and 102 that are alternately arranged along the second direction Y, near the first bus electrode 103, are all covered by the first insulating layer 115. This helps ensure that the first insulating layer 115 is located on the surface of the fourth part 112, reducing the high requirement for alignment accuracy between the first insulating layer 115 and the fourth part 112. In other words, it expands the process window for forming the first insulating layer 115, thereby reducing the difficulty of fabricating the first insulating layer 115. Similarly, the portions of the first fine gates 101 and 102 that are alternately arranged along the second direction Y, near the second bus electrode 104, are all covered by the second insulating layer 125. This helps ensure that the second insulating layer 125 is located on the surface of the second part 121, reducing the high requirement for alignment accuracy between the second insulating layer 125 and the second part 121. In other words, it expands the process window for forming the second insulating layer 125, thereby reducing the difficulty of fabricating the second insulating layer 125.

[0087] The part corresponding to the fourth part 112 in the first part 111 refers to the part in the first part 111 that is directly opposite to the fourth part 112 along the second direction Y, or in other words, the part in the first part 111 whose orthographic projection coincides with the orthographic projection of the fourth part 112, with the plane perpendicular to the second direction Y as the projection plane; the part corresponding to the second part 121 in the fifth part 122 refers to the part in the fifth part 122 that is directly opposite to the second part 121 along the second direction Y, or in other words, the part in the fifth part 122 whose orthographic projection coincides with the orthographic projection of the second part 121, with the plane perpendicular to the second direction Y as the projection plane.

[0088] Furthermore, when the first insulating layer 115 extends along the second direction Y, the first insulating portion 135 also extends along the second direction Y, and the first insulating layer 115 can be regarded as including two strip-shaped first insulating portions 135; when the second insulating layer 125 extends along the second direction Y, the second insulating portion 145 extends along the second direction Y, and the second insulating layer 125 can be regarded as including two strip-shaped second insulating portions 145.

[0089] The following combination Figure 9 and Figure 10 A detailed example illustrating the arrangement of the insulating layer 105 is provided. Among other things, Figure 9This is a partial top view of a fifth type of back contact battery provided in an embodiment of the present disclosure; Figure 10 for Figure 9 The diagram shows a top view of a battery with an added insulating layer in the back contact section.

[0090] In some embodiments, in conjunction with reference Figure 9 and Figure 10 The insulating layer 105 may include a plurality of first insulating bars 155 located in the first region 110 and arranged along the second direction Y, and a plurality of second insulating bars 165 located in the second region 120 and arranged along the second direction Y; wherein, the first insulating bar 155 is disposed between the battery substrate 100 and the first bus electrode 103, and the second insulating bar 165 is disposed between the battery substrate 100 and the second bus electrode 104.

[0091] Thus, the first insulating strip 155 is not only located on the surface of the fourth part 112, but the orthographic projections of the first insulating strip 155 and the first busbar 103 on the battery substrate 100 intersect, and the first insulating strip 155 corresponds one-to-one with a plurality of second fine grids 102 spaced apart along the second direction Y; the second insulating strip 165 is not only located on the surface of the second part 121, but the orthographic projections of the second insulating strip 165 and the second busbar 104 on the battery substrate 100 intersect, and the second insulating strip 165 corresponds one-to-one with a plurality of first fine grids 101 spaced apart along the second direction Y.

[0092] Based on this, the first portion 111 located on the first region 110 will not be completely covered by the first insulating strip 155. When the first solder strip is electrically connected to the first bus electrode 103, it can also be electrically connected to at least a portion of the first portions 111, which is beneficial to improving the carrier collection efficiency of the first solder strip. Moreover, when a grid break occurs at the connection between the first bus electrode 103 and the first portion 111, the electrical connection between the first solder strip and both the first bus electrode 103 and the first portion 111 helps to prevent some carriers in the first fine grid 101 from being unable to be effectively collected.

[0093] The fifth section 122 located on the second region 120 is not completely covered by the second insulating strip 165. When the second solder strip is electrically connected to the second bus electrode 104, it can also be electrically connected to at least a portion of the fifth sections 122, which helps improve the carrier collection efficiency of the second solder strip. Furthermore, when a grid break occurs at the connection between the second bus electrode 104 and the fifth section 122, the electrical connection between the second solder strip and both the second bus electrode 104 and the fifth section 122 helps prevent some carriers in the second fine grid 102 from failing to be effectively collected.

[0094] In some cases, a first insulating strip 155 may be provided between the fourth part 112 and the first bus electrode 103. In this case, there is no gap between the fourth part 112 and the first bus electrode 103 along the first direction X. In other words, the orthographic projections of the second fine grid 102 and the first bus electrode 103 on the battery substrate 100 intersect. However, the fourth part 112 and the first bus electrode 103 are spaced apart by the first insulating strip 155 along the third direction Z to prevent the second fine grid 102 from intersecting with the first bus electrode 103. Electrical connection; a second insulating strip 165 is provided between the second part 121 and the second bus electrode 104, so there is no gap between the second part 121 and the second bus electrode 104 along the first direction X. In other words, the orthogonal projections of the first fine grid 101 and the second bus electrode 104 on the battery substrate 100 intersect, but the second part 121 and the second bus electrode 104 are spaced apart by the second insulating strip 165 along the third direction Z to avoid electrical connection between the first fine grid 101 and the second bus electrode 104.

[0095] In other cases, in the second fine grid, there is a gap between the fourth part and the first bus electrode along the first direction, i.e., the fourth part has an opening, and the first insulating strip is located not only on the surface of the fourth part but also at the opening of the fourth part; in the first fine grid, there is a gap between the second part and the second bus electrode along the first direction, i.e., the second part has an opening, and the second insulating strip is located not only on the surface of the second part but also at the opening of the second part. In other words, the first insulating strip can be considered as Figure 7 The two adjacent first insulating blocks 1351 shown along the first direction also have a connecting portion, and the two first insulating blocks 1351 and the connecting portion together form a strip structure; the second insulating strip can be regarded as Figure 7 The two adjacent second insulating blocks 1451 shown in the first direction also have a connecting portion, and the two second insulating blocks 1451 and the connecting portion together form a strip structure.

[0096] In the above embodiments, reference is made to Figure 11 or Figure 12 The back contact battery may also include a reflective layer 106. In this way, for light incident on the battery substrate 100 that has not yet been absorbed and utilized, the reflective layer 106 can reflect that part of the light back into the battery substrate 100, so that that part of the light is eventually absorbed and utilized, thereby improving the light absorption and utilization rate of the back contact battery.

[0097] Figure 11 for Figure 8 The diagram shows a first cross-sectional structure of the back contact battery along the second cross-section direction BB1. Figure 12 for Figure 8 The diagram shows a second cross-sectional structure of the back contact battery along the second cross-sectional direction BB1.

[0098] In some cases, in conjunction with references Figure 8 and Figure 11 The reflective layer 106 can be located on the side of the insulating layer 105 away from the battery substrate 100. For example, the orthographic projection of the reflective layer 106 on the battery substrate 100 can coincide with the orthographic projection of the insulating layer 105 on the battery substrate 100, which is beneficial to form the insulating layer 105 and the reflective layer 106 by using a mask with the same pattern, thereby reducing the manufacturing cost of the back contact battery.

[0099] In some cases, in conjunction with references Figure 8 and Figure 12 The reflective layer 106 may be located on the surface jointly formed by the insulating layer 105 and the first bus electrode 103, and / or on the surface jointly formed by the insulating layer 105 and the second bus electrode 104. In other words, unlike the insulating layer 105 which is only located in a part of the first region 110, the reflective layer 106 may be located in the entire first region 110, that is, the orthogonal projection of the reflective layer 106 on the battery substrate 100 may coincide with the first region 110; and / or, unlike the insulating layer 105 which is only located in a part of the second region 120, the reflective layer 106 may be located in the entire second region 120, that is, the orthogonal projection of the reflective layer 106 on the battery substrate 100 may coincide with the second region 120.

[0100] In this way, it can also be electrically connected to at least a portion of the fifth section 122, which is beneficial to improving the carrier collection efficiency of the second solder strip 134. Moreover, when a grid break occurs at the connection between the second bus electrode 104 and the fifth section 122, the electrical connection between the second solder strip 134 and both the second bus electrode 104 and the fifth section 122 helps to prevent some carriers in the second fine grid 102 from being unable to be effectively collected.

[0101] In some embodiments, for the same back contact battery, the reflective layer 106 may be located in the entire first region 110 and the entire second region 120; or, for the same back contact battery, the reflective layer 106 may be located in the entire first region 110 and a portion of the second region 120; or, for the same back contact battery, the reflective layer 106 may be located in a portion of the first region 110 and the entire second region 120.

[0102] In the above scenario, the material of the reflective layer 106 may include at least one of the following metals: silver, aluminum, copper, tin, gold, lead, or nickel.

[0103] The following combination Figure 1 , Figure 3 and Figure 13 The following provides a detailed example illustrating the configuration of the insulating layer 105. Figure 13 for Figure 3 The diagram shows a cross-sectional structure of the back contact battery along the third section direction CC1.

[0104] In some embodiments, in conjunction with reference Figure 1 and Figure 3 The insulating layer 105 may be located on the surface of the third part 131 and the surface of the sixth part 132; Reference Figure 13 The back contact battery may further include a reflective layer 106 located on the side of the insulating layer 105 away from the battery substrate 100. In other words, the reflective layer 106 and the insulating layer 105 are located in the third region 130.

[0105] Thus, the first bus electrode 103 and the second bus electrode 104 are spaced apart by an insulating layer 105 along the first direction X, which can effectively prevent the first bus electrode 103 and the second bus electrode 104 from being electrically connected. In addition, the reflective layer 106 can improve the light absorption and utilization rate of the back contact battery.

[0106] In some cases, the orthographic projection of the reflective layer 106 onto the battery substrate 100 may coincide with the orthographic projection of the insulating layer 105 onto the battery substrate 100, meaning that the coverage areas of the reflective layer 106 and the insulating layer 105 on the battery substrate 100 are the same. In other cases, the orthographic projection of the reflective layer onto the battery substrate may lie within the orthographic projection of the insulating layer onto the battery substrate, meaning that the orthographic projection area (i.e., coverage area) of the reflective layer onto the battery substrate is smaller than the orthographic projection area (i.e., coverage area) of the insulating layer onto the battery substrate.

[0107] In some cases, the back contact battery may also include: insulating adhesive ( Figure 3 (Not shown in the image), located on the surfaces of the second part 121 and the fourth part 112. Thus, the insulating adhesive can prevent the first bus electrode 103 from electrically connecting to the second fine grid 102, and prevent the second bus electrode 104 from electrically connecting to the first fine grid 101. Furthermore, the insulating layer 105 can prevent the first bus electrode 103 from electrically connecting to the second bus electrode 104, thereby reducing the risk of internal short circuits in the back contact battery in multiple ways.

[0108] In some cases, the material of the reflective layer 106 includes at least one of the following metals: silver, aluminum, copper, tin, gold, lead, or nickel.

[0109] In some cases, along the first direction X, the width W3 of the third zone 130 can be greater than the width W1 of the first zone 110.

[0110] In some cases, along the first direction X, the width W3 of the third zone 130 can be greater than the width W2 of the second zone 120.

[0111] Regardless of whether the width W3 of the third region 130 is greater than the width W1 of the first region 110 or the width W2 of the second region 120, when the reflective layer 106 is located in the third region 130, it is beneficial to have more areas of the surface of the current-carrying components in the back contact battery, i.e., the back side, where the reflective layer 106 is provided. This allows more light that is not absorbed by the battery substrate 100 to be reflected back into the battery substrate 100, thereby further improving the light absorption and utilization rate of the back contact battery.

[0112] Furthermore, in the same back-contact battery, the width W3 of the third region 130 can be greater than both the width W1 of the first region 110 and the width W2 of the second region 120. In practical applications, the width of the third region can be greater than only the width of either the first or the second region.

[0113] In some cases, along the first direction X, the width W1 of the first region 110 or the width W2 of the second region 120 can be 0.2cm to 1cm, for example, 0.2cm to 0.5cm or 0.5cm to 1cm. Thus, when the reflective layer 106 is designed to be located in the third region 130, both the width W1 of the first region 110 and the width W2 of the second region 120 can be used to characterize the spacing between two adjacent third regions 130, that is, the spacing of the reflective layers 106 between two adjacent third regions 130. Based on this, designing the width W1 of the first region 110 or the width W2 of the second region 120 to be 0.2cm to 1cm helps ensure that the spacing of the reflective layers 106 between two adjacent third regions 130 is appropriate, thereby avoiding electrical connection between the first bus electrode 103 and the second bus electrode 104.

[0114] It should be noted that in the same back contact battery, the width W1 of the first region 110 and the width W2 of the second region 120 can both be between 0.2cm and 1cm. Based on this, the width W1 of the first region 110 and the width W2 of the second region 120 can be equal or have some difference.

[0115] Optionally, the width W1 of the first zone 110 or the width W2 of the second zone 120 can be 0.2cm, 0.25cm, 0.3cm, 0.35cm, 0.4cm, 0.45cm, 0.5cm, 0.55cm, 0.6cm, 0.65cm, 0.7cm, 0.75cm, 0.8cm, 0.85cm, 0.9cm, 0.95cm or 1cm, etc.

[0116] In some cases, the width W3 of the third region 130 along the first direction X can be 0.5cm to 1.2cm, for example, it can be 0.5cm to 0.8cm, 0.8cm to 1cm, or 1cm to 1.2cm. Thus, when the reflective layer 106 is designed to be located in the third region 130, designing the width W3 of the third region 130 to be 0.5cm to 1.2cm helps ensure that a large area on the back side of the back contact battery is covered with the reflective layer 106, thereby maximizing the absorption and utilization rate of light by the back contact battery.

[0117] Optionally, the width W3 of the third zone 130 can be 0.5cm, 0.55cm, 0.6cm, 0.65cm, 0.7cm, 0.75cm, 0.8cm, 0.85cm, 0.9cm, 0.95cm, 1cm, 1.05cm, 1.1cm, 1.15cm, or 1.2cm, etc.

[0118] In some cases, along the third direction Z, the thickness H1 of the insulating layer 105 can be less than the thickness H2 of the reflective layer 106, where the third direction Z is the thickness direction of the battery substrate 100. Thus, while achieving electrical isolation with the insulating layer 105, controlling the thickness H1 of the insulating layer 105 to be smaller helps to achieve a thinner back-contact battery; simultaneously, the larger thickness H2 of the reflective layer 106 compared to the thickness H1 of the insulating layer 105 helps to control the reflective layer 106 to have good optical performance.

[0119] In some cases, the thickness H1 of the insulating layer 105 along the third direction Z can be 20nm~50nm, for example, 20nm~30nm, 30nm~40nm, or 40nm~50nm. This is beneficial for the insulating layer 105 to achieve both good electrical isolation and help to make the back contact battery thinner.

[0120] Optionally, the thickness H1 of the insulating layer 105 can be 20nm, 21nm, 22nm, 23nm, 24nm, 25nm, 26nm, 27nm, 28nm, 29nm, 30nm, 31nm, 32nm, 33nm, 34nm, 35nm, 36nm, 37nm, 38nm, 39nm, 40nm, 41nm, 42nm, 43nm, 44nm, 45nm, 46nm, 47nm, 48nm, 49nm, or 50nm, etc.

[0121] In some cases, along the third direction Z, the thickness H2 of the reflective layer 106 can be 200nm~300nm, for example, 200nm~250nm or 250nm~300nm. This helps to improve the matching degree between the thickness H2 of the reflective layer 106 and the wavelength of light, thereby improving the reflective effect of the reflective layer 106 on light, so that more light is reflected again into the battery substrate 100.

[0122] Optionally, the thickness H2 of the reflective layer 106 can be 200nm, 205nm, 210nm, 215nm, 220nm, 225nm, 230nm, 235nm, 240nm, 245nm, 250nm, 255nm, 260nm, 265nm, 270nm, 275nm, 280nm, 285nm, 290nm, 295nm, or 300nm, etc.

[0123] The above example, using the insulating layer 105 and reflective layer 106 located in the third region 130, provides a detailed illustration of the widths of the first region 110, the second region 120, and the third region 130, as well as the thicknesses of the insulating layer 105 and the reflective layer 106. In practical applications, Figure 2 , Figure 7 , Figure 8 and Figure 10 In the back-contact battery shown, the widths of the first region 110, the second region 120, and the third region 130, as well as the insulating layer 105 and the reflective layer 106 (see reference). Figure 11 The thickness of both can be referred to the above description, and will not be repeated here.

[0124] In summary, based on increasing the distribution density of the first fine grid 101 and the second fine grid 102 in the back contact battery, in some cases, the insulating layer 105 located on the surface of the fourth part 112 can prevent the first bus electrode 103 from being electrically connected to the second fine grid 102, and the insulating layer 105 located on the surface of the second part 121 can prevent the second bus electrode 104 from being electrically connected to the first fine grid 101; or, in some cases, the insulating layer 105 located on the surface of the third part 131 and the surface of the sixth part 132 can prevent the first bus electrode 103 from being electrically connected to the second bus electrode 104. Moreover, compared to using insulating adhesive to avoid internal short circuits in the back contact battery, the insulating layer 105, which is made of at least one of silicon oxide or magnesium fluoride, has a lower coefficient of thermal expansion. This effectively prevents the back contact battery from warping due to the insulating layer 105 when it undergoes high and low temperatures, thus improving the structural stability of the back contact battery. On the other hand, the insulating layer 105, which is made of at least one of silicon oxide or magnesium fluoride, has higher density, providing better protection for the back contact battery and improving its anti-PID performance.

[0125] This disclosure provides a method for manufacturing a back contact battery, used to form the back contact battery provided in the foregoing embodiments. The manufacturing method of the back contact battery provided in one embodiment of this disclosure will be described in detail below with reference to the accompanying drawings. It should be noted that parts that are the same as or corresponding to those in the foregoing embodiments can be referred to the corresponding descriptions in the foregoing embodiments, and will not be repeated hereafter.

[0126] Reference Figure 14 as well as Figures 1 to 3 , Figure 14 This is a process flow diagram of a method for manufacturing a back contact battery according to an embodiment of the present disclosure. The method for manufacturing a back contact battery may include at least the following steps: S1: Obtain a battery substrate 100, which includes a first region 110 and a second region 120 arranged alternately along a first direction X, and a third region 130 located between the first region 110 and the second region 120.

[0127] S2: A first fine grid 101 and a second fine grid 102 are alternately arranged along a second direction Y on a battery substrate 100. The second direction Y is the direction that intersects with the first direction X. The first fine grid 101 includes a first part 111 located in a first region 110, a second part 121 located in a second region 120, and a third part 131 located in a third region 130. The second fine grid 102 includes a fourth part 112 located in a first region 110, a fifth part 122 located in a second region 120, and a sixth part 132 located in a third region 130.

[0128] S3: A first bus electrode 103, a second bus electrode 104, and an insulating layer 105 are formed on a battery substrate 100, which are alternately arranged along a first direction X. The first bus electrode 103 is located in a first region 110 and connected to a first part 111. The second bus electrode 104 is located in a second region 120 and connected to a fifth part 122. The material of the insulating layer 105 includes at least one of silicon oxide or magnesium fluoride. The insulating layer 105 is located on the surface of the second part 121 and the surface of the fourth part 112, or on the surface of the third part 131 and the surface of the sixth part 132.

[0129] Thus, by completing the fabrication of the insulating layer 105 during the manufacturing process of the back contact battery, electrical connections between the first bus electrode 103 and the second fine grid 102, and between the second bus electrode 104 and the first fine grid 101, are avoided during the manufacturing process; or, electrical connections between the first bus electrode 103 and the second bus electrode 104 are avoided during the manufacturing process. In other words, internal short circuits in the back contact battery are avoided during the manufacturing process, and the material of the insulating layer 105, including at least one of silicon oxide or magnesium fluoride, effectively prevents warping of the back contact battery caused by the insulating layer, thereby improving the structural stability of the back contact battery. Moreover, when subsequently achieving electrical connections between two adjacent back contact batteries, the insulating layer 105 helps reduce the risk of short circuits between the solder strip and the back contact battery.

[0130] In some embodiments, reference Figure 2 , Figure 7 , Figure 8 or Figure 10 In forming the first fine gate 101 (reference) Figure 1 ) and second fine gate 102 (reference) Figure 1 After that, before forming the first bus electrode 103 and the second bus electrode 104, an insulating layer 105 is formed on the surface of the second part 121 and the surface of the fourth part 112.

[0131] In other words, the insulating layer 105 is manufactured after the formation of the fine grid and before the formation of the bus electrode. This allows for early electrical isolation of the portions of the first fine grid 101 and the second fine grid 102 that are prone to short-circuiting with the bus electrode. Subsequently, when forming the first bus electrode 103 and the second bus electrode 104, the alignment accuracy requirements for the first bus electrode 103 and the second bus electrode 104 on the battery substrate 100 can be reduced, thus increasing the process window for forming the first bus electrode 103 and the second bus electrode 104 and reducing the fabrication difficulty of the first bus electrode 103 and the second bus electrode 104. The fine grid includes the first fine grid 101 and the second fine grid 102, and the bus electrode includes the first bus electrode 103 and the second bus electrode 104.

[0132] The steps for forming the insulating layer 105 are illustrated in detail below.

[0133] In some cases, refer to Figure 7 or Figure 8The step of forming the insulating layer 105 may include: forming a first insulating layer 115 on the first region 110, and forming a second insulating layer 125 on the second region 120. The first insulating layer 115 may include two first insulating portions 135 located on opposite sides of the first bus electrode 103, with the first insulating portions 135 at least located on the surface of the fourth portion 112; the second insulating layer 125 may include two second insulating portions 145 located on opposite sides of the second bus electrode 104, with the second insulating portions 145 at least located on the surface of the second portion 121.

[0134] It should be noted that the specific structure of the first insulating layer 115 and the second insulating layer 125 can be referred to the corresponding description of the foregoing embodiments, and will not be repeated here.

[0135] In some cases, refer to Figure 10 The step of forming the insulating layer 105 may include: forming a plurality of first insulating strips 155 arranged in the second direction Y on the first region 110, and forming a plurality of second insulating strips 165 arranged in the second direction Y on the second region 120.

[0136] It should be noted that the specific construction of the first insulating strip 155 and the second insulating strip 165 can be referred to the corresponding description of the foregoing embodiments, and will not be repeated here.

[0137] In some embodiments, reference Figure 3 After forming the first bus electrode 103 and the second bus electrode 104, and before forming the insulating layer 105, the manufacturing method of the back contact battery may further include: forming a mask (not shown in the figure) on the first region 110 and the second region 120; the step of forming the insulating layer 105 may include: in the first fine grid 101 (refer to Figure 1 ), second fine grid 102 (reference) Figure 1 The surface formed by the mask and the mask together forms an initial insulating layer (not shown in the figure); the mask is removed, and the remaining initial insulating layer 175 on the third region 130 is the insulating layer 105.

[0138] In this way, no specific pattern needs to be designed on the mask, that is, the manufacturing of the insulating layer 105 and the reflective layer 106 can be completed simultaneously without obtaining a mask with a specific pattern. This helps to reduce the cost of obtaining the mask and simplify the manufacturing process of the insulating layer 105 and the reflective layer 106.

[0139] In the above embodiments, reference is made to Figure 11 or Figure 12The manufacturing method of the back contact battery may further include forming a reflective layer 106 on the side of the insulating layer 105 away from the battery substrate 100. It should be noted that the relative positional relationship between the insulating layer 105 and the reflective layer 106, as well as the specific structure of the insulating layer 105 and the reflective layer 106, can be referred to the corresponding descriptions in the foregoing embodiments, and will not be repeated here.

[0140] This disclosure provides an apparatus for manufacturing a back contact battery, used to form the back contact battery provided in the foregoing embodiments, or for implementing the manufacturing method of the back contact battery provided in the foregoing embodiments. The apparatus for manufacturing a back contact battery according to an embodiment of this disclosure will be described in detail below with reference to the accompanying drawings. It should be noted that parts that are the same as or corresponding to those in the foregoing embodiments can be referred to the corresponding descriptions in the foregoing embodiments, and will not be repeated hereafter.

[0141] Reference Figure 15 ,as well as Figures 1 to 3 , Figure 15 This is a functional module diagram of a back contact battery manufacturing apparatus according to an embodiment of the present disclosure. The back contact battery manufacturing apparatus includes: an acquisition module 109 for acquiring a battery substrate 100, the battery substrate 100 including a first region 110 and a second region 120 alternately arranged along a first direction X, and a third region 130 located between the first region 110 and the second region 120; and a first manufacturing module 119 for forming a first fine grid 101 and a second fine grid 102 alternately arranged along a second direction Y on the battery substrate 100, the second direction Y being a direction intersecting the first direction X; wherein the first fine grid 101 includes a first portion 111 located in the first region 110, a second portion 121 located in the second region 120, and a third portion 131 located in the third region 130. The second fine grid 102 includes a fourth portion 112 located in the first region 110, a fifth portion 122 located in the second region 120, and a sixth portion 132 located in the third region 130; the second manufacturing module 129 is used to form a first bus electrode 103, a second bus electrode 104, and an insulating layer 105 arranged alternately along the first direction X on the battery substrate 100. The first bus electrode 103 is located in the first region 110 and connected to the first portion 111, and the second bus electrode 104 is located in the second region 120 and connected to the fifth portion 122; the material of the insulating layer 105 includes at least one of silicon oxide or magnesium fluoride; the insulating layer 105 is located on the surface of the second portion 121 and the surface of the fourth portion 112, or on the surface of the third portion 131 and the surface of the sixth portion 132.

[0142] Thus, the back contact battery manufacturing apparatus can not only manufacture back contact batteries, but also avoid internal short circuits during the manufacturing process. Furthermore, the design of the insulating layer 105, which includes at least one of silicon oxide or magnesium fluoride, effectively prevents warping of the back contact battery due to the insulating layer, thereby improving the structural stability of the back contact battery. Moreover, when subsequently establishing electrical connections between two adjacent back contact batteries, the insulating layer 105 helps reduce the risk of short circuits between the solder strip and the back contact battery.

[0143] This disclosure provides a stacked battery, including the back contact battery provided in the foregoing embodiments, or the back contact battery formed by the manufacturing method of the back contact battery provided in the foregoing embodiments, or the back contact battery formed by the manufacturing apparatus of the back contact battery provided in the foregoing embodiments. The stacked battery provided in one embodiment of this disclosure will be described in detail below with reference to the accompanying drawings. It should be noted that the parts that are the same as or corresponding to those in the foregoing embodiments can be referred to the corresponding descriptions in the foregoing embodiments, and will not be repeated hereafter.

[0144] refer to Figure 16 , Figure 16 This is a partial cross-sectional structural diagram of a tandem solar cell provided in an embodiment of the present disclosure. The tandem solar cell (TSC) includes: a crystalline silicon bottom cell 139, which is a back contact cell provided in the aforementioned embodiment, or a back contact cell formed by the manufacturing method of the back contact cell provided in the aforementioned embodiment, or a back contact cell formed by the manufacturing apparatus of the back contact cell provided in the aforementioned embodiment; and a perovskite top cell 149, which is located on one side of the crystalline silicon bottom cell 139.

[0145] In some embodiments, the perovskite top cell 149 may include: a stacked first transport layer, a perovskite substrate, a second transport layer, and a transparent conductive layer. The first transport layer is disposed opposite to the crystalline silicon bottom cell 139.

[0146] In some examples, the first transport layer can be either an electron transport layer or a hole transport layer, and the second transport layer can be either an electron transport layer or a hole transport layer.

[0147] In some embodiments, the perovskite top cell 149 has a wider bandgap than the crystalline silicon bottom cell 139. Therefore, stacking the perovskite top cell 149 on top of the crystalline silicon bottom cell 139 can give the stacked cell a wider spectral response range, thereby maximizing the utilization of solar energy and improving the efficiency of the stacked cell.

[0148] In some embodiments, the tandem solar cell may further include an intermediate connecting layer (not shown in the figure), which connects the crystalline silicon bottom cell 139 and the perovskite top cell 149.

[0149] In some cases, an intermediate connecting layer is used to enable carrier transport between the crystalline silicon bottom cell 139 and the perovskite top cell 149. This layer is typically a tunnel junction or a very thin composite layer of metal or transparent electrodes. Optionally, the intermediate connecting layer can be a transparent conductive oxide, which possesses excellent optoelectronic properties, high photon transmittance, and high conductivity, thereby enabling the perovskite top cell 149 and the crystalline silicon bottom cell 139 to maintain good ohmic contact.

[0150] In some cases, the first and second bus electrodes in the back contact cell of the crystalline silicon bottom cell 139 can also serve as an intermediate connection layer to achieve electrical connection with the perovskite top cell 149. Electrical connection between the two actually means that both are made of conductive materials, and they are directly contacted or connected via other conductive materials. Therefore, when the tandem cell is in power generation mode, there is an electrical connection between them.

[0151] This disclosure provides a photovoltaic module, which includes multiple back-contact cells as provided in the foregoing embodiments, or back-contact cells formed by a manufacturing method of multiple back-contact cells as provided in the foregoing embodiments, or back-contact cells formed by a manufacturing apparatus of multiple back-contact cells as provided in the foregoing embodiments, or multiple tandem cells as provided in the foregoing embodiments. The photovoltaic module is used to convert received light energy into electrical energy. It should be noted that the parts that are the same as or corresponding to those in the foregoing embodiments can be referred to the corresponding descriptions in the foregoing embodiments, and will not be repeated hereafter.

[0152] Reference Figure 17 , Figure 18 as well as Figures 1 to 3 The photovoltaic module includes: a series of back contact cells 40 connected together, or a series of back contact cells 40 formed by a manufacturing method of back contact cells provided in the foregoing embodiments, or a series of back contact cells 40 formed by a manufacturing apparatus of back contact cells provided in the foregoing embodiments, or a series of stacked cells provided in the foregoing embodiments; an encapsulation layer 41 for covering the surface of the cell string; and a cover plate 42 for covering the surface of the encapsulation layer 41 facing away from the cell string.

[0153] in, Figure 17 This is a partial three-dimensional schematic diagram of a cell string in a photovoltaic module provided in an embodiment of the present disclosure; Figure 18 This is a partial cross-sectional schematic diagram of a photovoltaic module provided in an embodiment of the present disclosure.

[0154] In some embodiments, the back contact battery 40 can be a monocrystalline silicon solar cell, a polycrystalline silicon solar cell, or an amorphous silicon solar cell.

[0155] In some cases, multiple back contact batteries 40 can be electrically connected via solder strips. It is important to note that this electrical connection actually means that both are made of conductive materials and are directly contacted or connected via other conductive materials. Therefore, when the back contact battery 40 is in a power-generating state, there is an electrical connection between them. The solder strips include a first solder strip 133 and a second solder strip 134.

[0156] Figure 17 and Figure 18 This illustration only shows one positional relationship between the back contact batteries 40, where electrodes of different polarities in each back contact battery 40 are located on the same surface, and the side of each back contact battery 40 with electrodes faces the same direction. Solder strips connect the same side of two adjacent back contact batteries 40 respectively. In other embodiments, the back contact batteries may also be arranged such that the sides of two adjacent back contact batteries with electrodes are located on different sides, in which case solder strips connect the different sides of the two adjacent back contact batteries.

[0157] In some embodiments, the back contact battery 40 is electrically connected in a single sheet or in multiple segments to form multiple battery strings, and the multiple battery strings are electrically connected in series and / or parallel. The back contact battery 40 can be a single sheet of battery or a slice of battery, where a slice of battery refers to a battery formed by cutting a single sheet of battery.

[0158] In some embodiments, the encapsulation layer 41 includes a first encapsulation layer and a second encapsulation layer. The first encapsulation layer covers one of the front or back sides of the back contact battery 40, and the second encapsulation layer covers the other of the front or back sides of the back contact battery 40. Specifically, at least one of the first encapsulation layer or the second encapsulation layer may be an organic encapsulation film such as polyvinyl butyral (PVB), ethylene-vinyl acetate copolymer (EVA), polyolefin thermoplastic elastomer (POE), or polyethylene glycol terephthalate (PET). Alternatively, at least one of the first encapsulation layer or the second encapsulation layer may also be an EP film, an EPE film, or a 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 sequentially stacking EVA film, POE film, and EVA film; and PVP film refers to a co-extruded film formed by stacking POE film, EVA film, and POE film. Co-extruded films can be prepared by sequentially extruding one or more raw materials onto another pre-made film during the film processing, or by bonding different types of pre-made films together.

[0159] In some cases, the first encapsulation layer and the second encapsulation layer still have a boundary line before lamination. After lamination, the photovoltaic module will no longer have the concept of a first encapsulation layer and a second encapsulation layer. That is, the first encapsulation layer and the second encapsulation layer have formed an integral encapsulation layer 41.

[0160] In some embodiments, the cover plate 42 can be a glass cover plate, a plastic cover plate, or other cover plate with light-transmitting function. Specifically, the surface of the cover plate 42 facing the encapsulation layer 41 can be an uneven surface or a textured surface containing multiple raised structures, thereby increasing the utilization rate of incident light. The cover plate 42 includes a first cover plate and a second cover plate, the first cover plate being opposite to the first encapsulation layer, and the second cover plate being opposite to the second encapsulation layer.

[0161] Those skilled in the art will understand that the above embodiments are specific examples of implementing this disclosure, and in practical applications, various changes in form and detail may be made without departing from the spirit and scope of the embodiments of this disclosure. Any person skilled in the art can make various modifications and alterations without departing from the spirit and scope of the embodiments of this disclosure; therefore, the scope of protection of the embodiments of this disclosure should be determined by the scope defined in the claims.

Claims

1. A back-contact battery, characterized in that, include: The battery substrate includes a first region and a second region arranged alternately along a first direction, and a third region located between the first region and the second region; A first fine grid and a second fine grid are disposed on the battery substrate and alternately arranged along a second direction, the second direction being the direction intersecting the first direction; wherein, the first fine grid includes a first part located in the first region, a second part located in the second region, and a third part located in the third region, and the second fine grid includes a fourth part located in the first region, a fifth part located in the second region, and a sixth part located in the third region; A first bus electrode and a second bus electrode are disposed on the battery substrate and alternately arranged along the first direction. The first bus electrode is located in the first region and connected to the first part, and the second bus electrode is located in the second region and connected to the fifth part. An insulating layer is located on the surface of the second part and the surface of the fourth part, or on the surface of the third part and the surface of the sixth part; the material of the insulating layer includes at least one of silicon oxide or magnesium fluoride.

2. The back contact battery according to claim 1, characterized in that, The insulating layer includes a first insulating layer located in the first region and a second insulating layer located in the second region; The first insulating layer includes two first insulating portions located on opposite sides of the first bus electrode, and the first insulating portions are located at least on the surface of the fourth portion; The second insulating layer includes two second insulating portions located on opposite sides of the second bus electrode, with the second insulating portions located at least on the surface of the second portions.

3. The back contact battery according to claim 2, characterized in that, The first insulating portion includes a plurality of first insulating blocks arranged along the second direction, the first insulating blocks being located on the surface of the fourth portion; the second insulating portion includes a plurality of second insulating blocks arranged along the second direction, the second insulating blocks being located on the surface of the second portion.

4. The back contact battery according to claim 2, characterized in that, The first insulating layer extends along the second direction, and along the second direction, the first insulating layer is also located on the surface of the portion of the first part corresponding to the fourth part; the second insulating layer extends along the second direction, and along the second direction, the second insulating layer is also located on the surface of the portion of the fifth part directly opposite the second part.

5. The back contact battery according to claim 1, characterized in that, The insulating layer includes a plurality of first insulating strips located in the first region and arranged along the second direction, and a plurality of second insulating strips located in the second region and arranged along the second direction; The battery substrate and the first busbar are provided with a first insulating strip, and the battery substrate and the second busbar are provided with a second insulating strip.

6. The back contact battery according to claim 5, characterized in that, The first insulating strip is provided between the fourth part and the first bus electrode, and the second insulating strip is provided between the second part and the second bus electrode.

7. The back contact battery according to any one of claims 2 to 6, characterized in that, It also includes a reflective layer; wherein the reflective layer is located on the side of the insulating layer away from the battery substrate; or, the reflective layer is located on the surface formed by the insulating layer and the first bus electrode, and / or, on the surface formed by the insulating layer and the second bus electrode.

8. The back contact battery according to claim 1, characterized in that, The insulating layer is located on the surface of the third part and the surface of the sixth part; the back contact battery further includes a reflective layer located on the side of the insulating layer away from the battery substrate.

9. The back contact battery according to claim 8, characterized in that, Along the first direction, the width of the first region or the width of the second region is 0.2cm to 1cm; and / or, the width of the third region is 0.5cm to 1.2cm.

10. The back contact battery according to claim 8, characterized in that, The thickness of the insulating layer is less than the thickness of the reflective layer.

11. The back contact battery according to claim 8, characterized in that, The thickness of the insulating layer is 20nm~50nm; and / or the thickness of the reflective layer is 200nm~300nm.

12. A method for manufacturing a back-contact battery, characterized in that, include: A battery substrate is obtained, the battery substrate comprising a first region and a second region arranged alternately along a first direction, and a third region located between the first region and the second region; A first fine grid and a second fine grid are alternately arranged along a second direction on the battery substrate, the second direction being the direction intersecting the first direction; wherein, the first fine grid includes a first part located in the first region, a second part located in the second region, and a third part located in the third region, and the second fine grid includes a fourth part located in the first region, a fifth part located in the second region, and a sixth part located in the third region; A first bus electrode, a second bus electrode, and an insulating layer are formed on the battery substrate, which are alternately arranged along the first direction. The first bus electrode is located in the first region and connected to the first part, and the second bus electrode is located in the second region and connected to the fifth part. The material of the insulating layer includes at least one of silicon oxide or magnesium fluoride; The insulating layer is located on the surface of the second part and the surface of the fourth part, or on the surface of the third part and the surface of the sixth part.

13. The method for manufacturing a back contact battery according to claim 12, characterized in that, After the first fine gate and the second fine gate are formed, and before the first bus electrode and the second bus electrode are formed, the insulating layer is formed on the surface of the second part and the surface of the fourth part.

14. The method for manufacturing a back contact battery according to claim 12, characterized in that, After forming the first bus electrode and the second bus electrode, and before forming the insulating layer, the method further includes: A mask is formed on the first region and the second region; The step of forming the insulating layer includes: forming an initial insulating layer on the surface formed by the first fine gate, the second fine gate, and the mask; removing the mask, and the remaining initial insulating layer located on the third region is the insulating layer.

15. The method for manufacturing a back-contact battery according to any one of claims 12 to 14, characterized in that, Also includes: A reflective layer is formed on the side of the insulating layer away from the battery substrate.

16. An apparatus for manufacturing a back-contact battery, characterized in that, include: An acquisition module is used to acquire a battery substrate, the battery substrate including a first region and a second region arranged alternately along a first direction, and a third region located between the first region and the second region; A first manufacturing module is configured to form a first fine grid and a second fine grid arranged alternately along a second direction on the battery substrate, the second direction being a direction intersecting the first direction; wherein, the first fine grid includes a first part located in the first region, a second part located in the second region, and a third part located in the third region, and the second fine grid includes a fourth part located in the first region, a fifth part located in the second region, and a sixth part located in the third region; The second manufacturing module is used to form a first busbar electrode, a second busbar electrode, and an insulating layer that are alternately arranged along the first direction on the battery substrate. The first busbar electrode is located in the first region and connected to the first part, and the second busbar electrode is located in the second region and connected to the fifth part. The material of the insulating layer includes at least one of silicon oxide or magnesium fluoride; The insulating layer is located on the surface of the second part and the surface of the fourth part, or on the surface of the third part and the surface of the sixth part.

17. A stacked battery, characterized in that, include: A crystalline silicon bottom battery, wherein the crystalline silicon bottom battery is a back contact battery as described in any one of claims 1 to 11, or a back contact battery formed by a manufacturing method of a back contact battery as described in any one of claims 12 to 15, or a back contact battery formed by a manufacturing apparatus of a back contact battery as described in claim 16. A perovskite top cell, wherein the perovskite top cell is located on one side of the crystalline silicon bottom cell.

18. A photovoltaic module, characterized in that, include: The battery string is formed by connecting a plurality of back contact batteries as described in any one of claims 1 to 11, or by connecting a plurality of back contact batteries formed by a method of manufacturing a back contact battery as described in any one of claims 12 to 15, or by connecting a plurality of back contact batteries formed by an apparatus for manufacturing a back contact battery as described in claim 16, or by connecting a plurality of stacked batteries as described in claim 17. An encapsulation layer is used to cover the surface of the battery string; A cover plate is used to cover the surface of the encapsulation layer that faces away from the battery string.

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