Photovoltaic module

Abstract

The invention relates to the technical field of solar cells, in particular to a photovoltaic module. In the embodiment of the invention, the fine grid group comprises a first part overlapped with the convergence piece and a second part except the first part. The size of the first part in the direction from the second surface side to the first surface side is configured to be smaller than the size of the second part in the direction from the second surface side to the first surface side, so that the height difference between the region provided with the confluence piece and the region not provided with the confluence piece can be reduced; therefore, in the lamination process of the photovoltaic module or when the photovoltaic module is subjected to an external acting force, the risk of subfissure of the battery piece caused by the fact that the confluence piece is pressed on the battery piece can be reduced, the reliability of the photovoltaic module can be improved, and the yield of the photovoltaic module can be improved. In addition, the size of the first part is smaller than that of the second part in the direction from the second surface side to the first surface side, so that the material consumption of the fine grid can be reduced, and the manufacturing cost is reduced.

Description

Technical Field

[0001] This application relates to the field of solar cell technology, and in particular to photovoltaic modules. Background Technology

[0002] As the photovoltaic industry pursues both efficiency and aesthetic appeal in its modules, related technologies are incorporating busbars that were previously exposed on the front or edges of the module to be hidden on the back. This increases the effective light-receiving area on the front, significantly improving screen-to-body ratio and photoelectric conversion efficiency, while achieving a clean, unobstructed appearance, making it suitable for diverse applications such as distributed power stations and building-integrated photovoltaics (BIPV). However, the reliability of photovoltaic modules still needs further improvement. Summary of the Invention

[0003] Therefore, it is necessary to provide a photovoltaic module to improve its reliability.

[0004] This application provides a photovoltaic module including multiple cell strings and a busbar. The cell strings have a first surface side and a second surface side disposed opposite to each other. Each cell string includes multiple cells connected in series, and each cell includes a fine grid array, with the fine grid array located at least on the second surface side. The busbar is located on the second surface side and is electrically connected to the multiple cell strings. The fine grid array includes a first portion overlapping the busbar and a second portion other than the first portion; the size of the first portion is smaller than the size of the second portion in the direction from the second surface side to the first surface side.

[0005] In some embodiments, the first portion includes multiple fine grids in a fine grid group located on the second surface side.

[0006] In some embodiments, the busbar has a groove on one side facing the plurality of battery strings; the orthographic projection of the first portion is located within the orthographic projection range of the groove along the direction from the second surface side to the first surface side.

[0007] In some embodiments, the first part includes a plurality of fine gates in a fine gate group located on the second surface side, and a portion of at least one fine gate in the fine gate group located on the second surface side; the fine gates in the plurality of fine gates in the fine gate group located on the second surface side are first fine gates, and the fine gates in the at least one fine gate in the fine gate group located on the second surface side are second fine gates; in the first part, along the arrangement direction of the fine gates located on the second surface side, at least one of the first fine gate and the last fine gate is a second fine gate, and the remaining fine gates are first fine gates.

[0008] In some embodiments, the second fine gate includes a first fine gate portion that overlaps with the busbar, and a second fine gate portion other than the first fine gate portion; the size of the second fine gate portion is larger than the size of the first fine gate portion in the direction from the second surface side to the first surface side.

[0009] In some embodiments, the first portion includes a middle portion and two edge portions located in the middle portion along the grid arrangement direction in the grid group located on the second surface side; the size of the middle portion is smaller than the size of the edge portions in the direction from the second surface side to the first surface side.

[0010] In some embodiments, the dimension of the first portion decreases linearly in the direction from the middle portion to the edge portion along the direction from the second surface side to the first surface side.

[0011] In some embodiments, in the fine grid of the first portion, the dimension of the preceding fine grid in the direction from the middle portion to the edge portion, in the direction from the second surface side to the first surface side, is greater than the dimension of the following fine grid in the direction from the second surface side to the first surface side.

[0012] In some embodiments, in the fine grid of the first portion, at least a portion of the fine grid's surface facing the busbar includes at least one of an inclined plane, a straight plane, and a curved surface; the inclined plane intersects with but is not perpendicular to the direction of the second surface side pointing to the first surface side, and the straight plane is perpendicular to the direction of the second surface side pointing to the first surface side.

[0013] In some embodiments, in the first portion of the fine grid, at least a portion of the fine grid has a cross-sectional shape including at least one of rectangular, arc-shaped, and trapezoidal shapes; the cross-section of the fine grid is perpendicular to the longitudinal extension direction of the fine grid.

[0014] In some embodiments, the ratio of the size of the first portion to the size of the second portion is 0.5 to 0.8 in the direction from the second surface side to the first surface side.

[0015] In some embodiments, the difference between the size of the second portion and the size of the first portion is 2 micrometers to 5 micrometers along the direction from the second surface side to the first surface side.

[0016] In some embodiments, in the direction from the second surface side to the first surface side, the first portion has a protrusion protruding toward the busbar, and the busbar has a recess located on the side of the busbar facing the first portion; in the direction from the second surface side to the first surface side, the orthographic projection of the protrusion is located within the orthographic projection range of the recess.

[0017] In some embodiments, in the battery string, the outermost battery cell is a first battery cell, and the battery cell adjacent to the first battery cell is a second battery cell; the busbar includes an edge busbar. The edge busbar is disposed on the first battery cell; or, the edge busbar is disposed on the second battery cell.

[0018] In some embodiments, the edge busbar is located in the middle of the cell where the edge busbar is located; or, the edge busbar is located at the edge of the cell where the edge busbar is located.

[0019] In some embodiments, the battery cell located in the middle of the battery string is the third battery cell; the busbar includes an intermediate busbar disposed on the third battery cell. The intermediate busbar is located in the middle of the third battery cell; or, the intermediate busbar is located at the edge of the third battery cell.

[0020] In some embodiments, the solar cell is a back-contact solar cell; the photovoltaic module further includes an electrical connector located on the second surface side, the solar cells in the solar cell string are connected by the electrical connector, the electrical connector includes a first electrical connector and a second electrical connector, the first electrical connector and the second electrical connector are alternately spaced on the solar cell along a first direction; the busbar is electrically connected to the first electrical connector and is insulated from the second electrical connector.

[0021] In some embodiments, the first electrical connector includes a first electrical connection portion overlapping the busbar and a second electrical connection portion other than the first electrical connection portion; the first electrical connection portion is recessed relative to the second electrical connection portion and is closer to the battery cell; and / or, the second electrical connector includes a third electrical connection portion overlapping the busbar and a fourth electrical connection portion other than the third electrical connection portion; the third electrical connection portion is recessed relative to the fourth electrical connection portion and is closer to the battery cell.

[0022] In some embodiments, the photovoltaic module further includes a first insulating member disposed on the side of the second electrical connector away from the solar cell, and the busbar is insulated from the second electrical connector by means of the first insulating member; the first insulating member includes a first insulating portion overlapping the busbar and a second insulating portion other than the first insulating portion; the first insulating portion is recessed compared to the second insulating portion and is closer to the solar cell.

[0023] In some embodiments, the solar cell is a tunnel oxide passivated contact solar cell; the photovoltaic module also includes electrical connectors, through which the solar cells in the cell string are connected, and the busbar is electrically connected to the electrical connectors.

[0024] In some embodiments, the busbar includes a first busbar and an electrical connector electrically connected to the first busbar is a third electrical connector; the third electrical connector includes a main body portion located on a first surface side and a bent portion connected to the main body portion; the bent portion is electrically connected to the first busbar, and the first busbar is insulated from the electrical connector located on a second surface side.

[0025] In some embodiments, the photovoltaic module further includes a second insulating member disposed on the side of the electrical connector located on the second surface side away from the solar cell, and the first busbar is insulated from the second surface side by means of the second insulating member; the second insulating member includes a third insulating portion overlapping the first busbar, and a fourth insulating portion other than the third insulating portion; the third insulating portion is recessed compared to the fourth insulating portion and is closer to the solar cell.

[0026] In the aforementioned photovoltaic module, the photovoltaic module includes at least multiple cell strings and a busbar. Each cell string includes multiple cells, and each cell includes a grid of fine grids located at least on the second surface side of the cell string. The busbar is located on the second surface side. The grid of fine grids includes a first portion overlapping the busbar, and a second portion other than the first portion; that is, the first portion is opposite to the busbar, while the second portion is not opposite to the busbar. By configuring the dimension of the first portion along the direction from the second surface side to the first surface side to be smaller than the dimension of the second portion along the direction from the second surface side to the first surface side, the height difference between the area where the busbar is located and the area where the busbar is not located can be reduced. This reduces the risk of microcracks in the cells caused by the busbar pressing on them during the lamination process of the photovoltaic module or when the photovoltaic module is subjected to external forces. This not only improves the reliability of the photovoltaic module but also its yield. Furthermore, since the first portion is smaller than the second portion along the direction from the second surface side to the first surface side, the amount of material used for the grid of fine grids can be reduced, lowering manufacturing costs.

[0027] Additional aspects and advantages of embodiments of this application will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of embodiments of this application. Attached Figure Description

[0028] Various other advantages and benefits will become apparent to those skilled in the art upon reading the detailed description of the embodiments described below. The accompanying drawings are for illustrative purposes only and are not intended to limit the scope of this application. Furthermore, the same reference numerals denote the same parts throughout the drawings. In the drawings:

[0029] Figure 1 This is a schematic diagram of the structure of a photovoltaic module in some embodiments of this application;

[0030] Figure 2 This is a partial structural diagram of the interaction between the battery string and the busbar in some embodiments of this application;

[0031] Figure 3 This is a partial structural diagram of the battery cell in some embodiments of this application;

[0032] Figure 4 This is a partial structural diagram of the interaction between the battery cell and the busbar in some embodiments of this application;

[0033] Figure 5 This is a partial structural diagram of the interaction between the battery cell and the busbar in some other embodiments of this application;

[0034] Figure 6 This is a partial structural diagram of the interaction between the battery cell and the busbar in some embodiments of this application;

[0035] Figure 7 This is a partial structural diagram of the interaction between the battery cell and the busbar in some embodiments of this application;

[0036] Figure 8 This is a schematic diagram of the structure of the second fine gate in some embodiments of this application;

[0037] Figure 9 This is a partial structural schematic diagram of the battery cell in some other embodiments of this application;

[0038] Figure 10 This is a partial structural schematic diagram of the battery cell in some embodiments of this application;

[0039] Figure 11 This is a partial structural diagram of the battery cell in some embodiments of this application;

[0040] Figure 12 This is a partial structural schematic diagram of the battery cell in some other embodiments of this application;

[0041] Figure 13 This is a partial structural diagram of the battery cell in some other embodiments of this application;

[0042] Figure 14 This is a partial structural diagram of the interaction between the battery cell and the busbar in some other embodiments of this application;

[0043] Figure 15 This is a partial structural diagram showing the interaction between the battery string, busbar, and electrical connector in some embodiments of this application;

[0044] Figure 16 This is a partial structural schematic diagram of the battery cell and electrical connector in some embodiments of this application;

[0045] Figure 17 This is a partial structural diagram showing the interaction between the battery cells, electrical connectors, and busbars in some embodiments of this application;

[0046] Figure 18 This is a partial structural diagram showing the interaction between the battery cell, the first electrical connector, and the busbar in some embodiments of this application.

[0047] Figure 19 This is a schematic diagram of the structure of the first electrical connector in some embodiments of this application;

[0048] Figure 20 This is a partial structural diagram showing the interaction between the battery cell, the second electrical connector, and the busbar in some embodiments of this application;

[0049] Figure 21This is a schematic diagram of the structure of the second electrical connector in some embodiments of this application;

[0050] Figure 22 This is a schematic diagram showing the interaction between the battery cell, electrical connector, busbar and first insulating member in some embodiments of this application;

[0051] Figure 23 This is a schematic diagram of the structure of the first insulating element in some embodiments of this application;

[0052] Figure 24 This is a partial structural diagram showing the interaction between the battery cells, electrical connectors, and busbars in other embodiments of this application;

[0053] Figure 25 This is a partial structural diagram showing the interaction between adjacent battery cells, the first busbar, and the third electrical connector in some embodiments of this application;

[0054] Figure 26 This is an exploded structural diagram showing the interaction between the first busbar and the second insulator in some embodiments of this application.

[0055] Explanation of reference numerals in the attached figures:

[0056] 1000 photovoltaic modules;

[0057] Battery strings 1100, 1100a; first surface side 1101; second surface side 1102; battery cells 1110, 1110a, 1110b, 1110c, 1110d, 1110e, 1110f, 1110', 1110''; first battery cell 11101; second battery cell 11102; third battery cell 11103; battery substrate 1111; fine grid groups 1112, 1112a, 1112b, 1112c, 1112d, 111 2e, 1112f, fine grids 11121, 11121', first fine grid x1, second fine grids x2, x2a, first fine grid portion x21, second fine grid portion x22, first portion P1, P1a, P1b, P1c, P1d, P1e, P1f, middle portion P11, P11a, P11b, edge portion P12, P12a, P12b, protrusion P121, second portion P2, first dimension h1, second dimension h2, third dimension h3, fourth dimension h4;

[0058] Busbars 1200, 1200a, 1200b, 1200c; groove 1201; recess 1202; edge busbar 1210; middle busbar 1220; first busbar 1230;

[0059] Electrical connector 1300, first electrical connector 1300a, first electrical connection part 1311, second electrical connection part 1312, second electrical connector 1300b, third electrical connection part 1321, fourth electrical connection part 1322, third electrical connector 1300c, main body part 1310, bending part 1320.

[0060] First insulating element 1400, first insulating part 1410, second insulating part 1420;

[0061] Second insulating component 1500, third insulating part 1510, fourth insulating part 1520;

[0062] Cover plate 1600;

[0063] Encapsulation layer 1700;

[0064] First direction F1, second direction F2, third direction F3. Detailed Implementation

[0065] To make the above-mentioned objectives, features, and advantages of this application more apparent and understandable, the specific embodiments of this application are described in detail below with reference to the accompanying drawings. Many specific details are set forth in the following description to provide a thorough understanding of this application. However, this application can be implemented in many other ways different from those described herein, and those skilled in the art can make similar modifications without departing from the spirit of this application. Therefore, this application is not limited to the specific embodiments disclosed below.

[0066] In the description of this application, it should be understood that if terms such as "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential" appear, these terms indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this application and simplifying the description, and 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 of this application.

[0067] Furthermore, where the terms "first" and "second" appear, these terms are for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined with "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this application, where the term "multiple" appears, "multiple" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0068] In this application, unless otherwise expressly specified and limited, the terms "installation," "connection," "joining," "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can be a mechanical connection or an electrical connection; they can be 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, unless otherwise expressly limited. It is worth noting that in the following description and the appended claims, "electrical connection" between one feature and another not only includes direct contact between the two features to form an electrical energy transmission or current transmission channel, but also includes an intermediate feature between the two features, which, along with the intermediate feature, forms an electrical energy transmission or current transmission channel to achieve electrical energy transmission or transmission. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0069] In this application, unless otherwise expressly specified and limited, the use of descriptions such as "above" or "below" the second feature indicates that the first and second features are in direct contact or indirect contact via an intermediate medium. Furthermore, "above," "on top of," and "over" the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. Similarly, "below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0070] It should be noted that if an element is referred to as being "fixed to" or "set on" another element, it can be directly on the other element or there may be an intervening element. If an element is considered to be "connected to" another element, it can be directly connected to the other element or there may be an intervening element. If so, the terms "vertical," "horizontal," "upper," "lower," "left," "right," and similar expressions used in this application are for illustrative purposes only and do not represent the only possible implementation.

[0071] In the accompanying drawings, the thicknesses of elements such as layers, films, regions, and substrates are exaggerated for clarity. Throughout the specification, the same reference numerals refer to the same elements. It should be understood that when an element such as a layer, film, region, or substrate is referred to as being "on" another element, it may be directly on the other element or there may be intervening elements. Conversely, when an element is referred to as being "directly on" another element, there are no intervening elements.

[0072] According to some embodiments of this application, please refer to Figure 1 and Figure 2 , Figure 1 This is a schematic diagram of the structure of the photovoltaic module 1000 in some embodiments of this application. Figure 2 This is a partial structural diagram of the interaction between the battery string 1100 and the busbar 1200 in some embodiments of this application. The embodiments of this application provide a photovoltaic module 1000, including multiple battery strings 1100 and busbar 1200. Figure 2 The diagram illustrates the approximate relationship between the battery string 1100 and the busbar 1200.

[0073] The battery string 1100 is a power generation unit formed by connecting multiple battery cells 1110 through a welding process. The battery cell 1110 can be a tunnel oxide passivated contact battery cell, a back contact battery cell, etc., and is not specifically limited here. It should be noted that... Figure 1 The diagram illustrates a power generation unit formed by connecting multiple back-contact solar cells through a welding process.

[0074] Combined with reference Figure 3 , Figure 3 This is a partial structural diagram of the battery cell 1110 in some embodiments of this application. The battery string 1100 has a first surface side 1101 and a second surface side 1102 disposed opposite to each other. The battery string 1100 includes a plurality of battery cells 1110 connected in series. The battery cell 1110 includes a fine grid group 1112. The fine grid group 1112 is located at least on the second surface side 1102.

[0075] The first surface side 1101 and the second surface side 1102 of the battery string 1100 are relative to the thickness direction of the battery string 1100. Figures 1 to 3For example, the first surface side 1101 and the second surface side 1102 of the battery string 1100 are arranged opposite each other along a first direction F1. The battery cell 1110 includes a battery substrate 1111 and a fine grid group 1112 disposed on the battery substrate 1111. The battery substrate 1111 includes a multi-layer functional structure combination, rather than a single conventional substrate (such as a silicon wafer). This multi-layer functional structure combination can be determined according to the different types of battery cells 1110, and will not be elaborated here. The fine grid group 1112 is a conductive collection composed of multiple fine grids 11121, that is, the fine grid group 1112 includes multiple fine grids 11121. The fine grid group 1112 is located at least on the second surface side 1102, that is, the fine grid group 1112 can be located on the second surface side 1102, or it can be located on the first surface side 1101 and the second surface side 1102. For example, when the solar cell 1110 is a tunneling oxide passivated contact solar cell, both the first surface side 1101 and the second surface side 1102 are provided with fine grid groups 1112. As another example, when the solar cell 1110 is a back contact solar cell, the second surface side 1102 is provided with fine grid groups 1112. In the embodiments of this application, the first surface side 1101 is the light-receiving surface side, and the second surface side 1102 is the back-lighting surface side. It should be noted that the light-receiving surface side and the back-lighting surface side are relative terms. The light-receiving surface side specifically refers to the surface on the solar cell substrate 1111 of the photovoltaic module 1000 that is primarily irradiated by sunlight.

[0076] Busbar 1200 is located on the second surface side 1102. Busbar 1200 is a conductive connector 1300 inside the photovoltaic module 1000. Exemplarily, busbar 1200 may be tin-plated copper strip or copper foil, without particular limitation herein.

[0077] Busbar 1200 is electrically connected to multiple battery strings 1100. That is, adjacent battery strings 1100 are electrically connected via busbar 1200 in the second direction F2 and / or the third direction F3. Busbar 1200 is used to realize series or parallel connection between adjacent battery strings 1100. The first direction F1, the second direction F2, and the third direction F3 intersect each other. Exemplarily, in this embodiment, the first direction F1, the second direction F2, and the third direction F3 are perpendicular to each other.

[0078] It should be noted that the electrical connection between the busbar 1200 and the multiple battery strings 1100 means that, since the busbar 1200 and the battery strings 1100 are conductive, they form a physical channel for the flow of photogenerated carriers through direct or indirect physical contact. When the battery cell 1110 is not in a power generation or power supply state, the photogenerated carriers are not effectively separated and driven to flow, and the photogenerated carriers do not flow through this physical channel. When the battery cell 1110 is in a power generation or power supply state, photogenerated carriers are generated within the battery cell 1110 and separated under the influence of its built-in electric field, allowing the photogenerated carriers to flow out through this physical channel.

[0079] Combined with reference Figure 4 , Figure 4 This is a partial structural diagram of the interaction between the battery cell 1110 and the busbar 1200 in some embodiments of this application. The fine grid group 1112 includes a first portion P1 that overlaps with the busbar 1200, and a second portion P2 excluding the first portion P1. Along the direction from the second surface side 1102 to the first surface side 1101, the size of the first portion P1 is smaller than the size of the second portion P2.

[0080] Since the fine grid group 1112 includes multiple fine grids 11121, that is, the first part P1 includes a portion of these multiple fine grids 11121, and the second part P2 includes another portion of these multiple fine grids 11121. Figure 4 For example, the first part P1 overlaps with the busbar 1200, which can be understood as the first part P1 overlapping with the busbar 1200 from the perspective of the first direction F1. However, from the perspective of the first direction F1, the second part P2 does not overlap with the busbar 1200. That is, it can be understood that the first part P1 is opposite to the busbar 1200, while the second part P2 is not opposite to the busbar 1200.

[0081] For example, in conjunction with reference Figure 3 The direction from the second surface side 1102 to the first surface side 1101 is parallel to the first direction F1. The dimension of the first part P1 along the direction from the second surface side 1102 to the first surface side 1101 is the dimension of the first part P1 along the first direction F1. The dimension of the second part P2 along the direction from the second surface side 1102 to the first surface side 1101 is the dimension of the second part P2 along the second direction F2. The dimension of the first part P1 along the first direction F1 is the first dimension h1, and the dimension of the second part P2 along the first direction F1 is the second dimension h2. The first dimension h1 is smaller than the second dimension h2. (Referring to a reference point...) Figure 4As can be seen, compared to the case where the first dimension h1 and the second dimension h2 are equal, since the first dimension h1 is smaller than the second dimension h2, the overall height of this part of the area after the busbar 1200 is set can be reduced, thereby reducing the height difference between different areas of the overall structure.

[0082] It should be noted that the height mentioned above refers to the dimension along the thickness direction of the battery string 1100, which can be understood as the dimension of the battery string 1100 along the first direction F1.

[0083] Therefore, by configuring the dimension of the first portion P1 along the direction from the second surface side 1102 to the first surface side 1101 to be smaller than the dimension of the second portion P2 along the same direction, the height difference between the area where the busbar 1200 is provided and the area where the busbar 1200 is not provided can be reduced. This reduces the risk of microcracks in the solar cell 1110 caused by the busbar 1200 pressing against it during the lamination process of the photovoltaic module 1000 or when the photovoltaic module 1000 is subjected to external forces. This not only improves the reliability of the photovoltaic module 1000 but also its yield. Furthermore, since the first portion P1 is smaller than the second portion P2 along the direction from the second surface side 1102 to the first surface side 1101, the material used for the fine grid 11121 can be reduced, lowering manufacturing costs.

[0084] Based on some embodiments of this application, please continue to refer to Figure 3 and Figure 4 The first part P1 includes multiple fine grids 11121 in the fine grid group 1112 located on the second surface side 1102. That is, the fine grids 11121 opposite to the busbar 1200 are all complete fine grids 11121, and from the perspective of the first direction F1, the fine grids 11121 opposite to the busbar 1200 fall completely within the range of the busbar 1200.

[0085] Thus, by setting the first part P1 to include multiple fine grids 11121 in the fine grid group 1112 located on the second surface side 1102, not only can the multiple fine grids 11121 fully support the busbar 1200, but it is also beneficial to control the size of both the busbar 1200 and the fine grids 11121, thereby facilitating manufacturing.

[0086] According to some embodiments of this application, please refer to Figure 5 , Figure 5This is a partial structural diagram of the interaction between the battery cell 1110 and the busbar 1200a in some other embodiments of this application. The busbar 1200a has a groove 1201 on the side facing the multiple battery strings 1100. Along the direction from the second surface side 1102 to the first surface side 1101, the orthographic projection of the first part P1 is located within the orthographic projection range of the groove 1201.

[0087] The busbar 1200a faces the side of the multiple battery strings 1100, that is, the side of the busbar 1200a facing the multiple battery strings 1100 along the first direction F1. The groove 1201 is a structure formed by recessing the surface of the busbar 1200a facing the multiple battery strings 1100 along the first direction F1 in a direction away from the multiple battery strings 1100. It should be noted that the term "recessed" here is only for the purpose of understanding the structure of the groove 1201 and does not impose specific limitations on the process of forming the groove 1201.

[0088] The orthographic projection of the first part P1 is located within the orthographic projection range of the groove 1201. That is, from the perspective of the first direction F1, the first part P1 can be seen to be located within the range of the groove 1201.

[0089] Because the busbar 1200a has a groove 1201, meaning the middle region of the busbar 1200a is thinner and the edge region is thicker, the thinner middle region of the busbar 1200a can form a flow channel with the battery cell 1110. The molten adhesive film can quickly fill from the middle to both sides, thereby reducing the risk of local cavities forming on the side of the busbar 1200a facing the multiple battery strings 1100 due to obstructed adhesive film flow. Simultaneously, this structure allows the pressure in the middle of the busbar 1200a to be more evenly distributed along the edge. Moreover, the thinner middle region of the busbar 1200a has stronger deformation capacity, further buffering pressure impacts and reducing local pressure acting on the battery cell 1110. Furthermore, by providing the groove 1201, the shape of the groove 1201 can also be used to position the busbar 1200a in the desired area.

[0090] According to some embodiments of this application, please refer to Figure 6 , Figure 6This is a partial structural diagram of the interaction between the battery cell 1110 and the busbar 1200b in some embodiments of this application. The first part P1 includes multiple fine grids 11121 in the fine grid group 1112 located on the second surface side 1102, and a portion of at least one fine grid 11121 in the fine grid group 1112 located on the second surface side 1102. The fine grid 11121 in the multiple fine grids 11121 in the fine grid group 1112 located on the second surface side 1102 is the first fine grid x1, and the fine grid 11121 in the at least one fine grid 11121 in the fine grid group 1112 located on the second surface side 1102 is the second fine grid x2. In the first part P1, along the arrangement direction of the fine grids 11121 located on the second surface side 1102, at least one of the first fine grid 11121 and the last fine grid 11121 is the second fine grid x2, and the remaining fine grids 11121 are the first fine grids x1.

[0091] The first fine gate x1 is a fine gate 11121 that completely overlaps with the busbar 1200b. The second fine gate x2 is a fine gate 11121 that partially overlaps with the busbar 1200b. For example, with... Figure 6 For example, from the perspective of the first direction F1, the first fine gate x1 is located within the range of the busbar 1200b, a portion of the second fine gate x2 is located within the range of the busbar 1200b, and another portion of the second fine gate x2 is located outside the range of the busbar 1200b. The arrangement direction of the fine gates 11121 located on the second surface side 1102 is parallel to the second direction F2. For example, with... Figure 6 For example, in the first part P1, along the second direction F2, both the first fine grid 11121 and the last fine grid 11121 are the second fine grid x2.

[0092] Thus, by setting the first fine gate x1 and the second fine gate x2, not only can the interfacial shear stress caused by thermal expansion and contraction be alleviated, reducing the risk of subsequent desoldering or breakage of the fine gate 11121, but the welding fault tolerance of the fine gate 11121 and the electrical connection can also be improved, and the process window for setting the bus 1200b can be expanded, which is beneficial to the manufacturing process.

[0093] According to some embodiments of this application, please refer to Figure 7 and Figure 8 , Figure 7 This is a partial structural diagram of the interaction between the battery cell 1110a and the busbar 1200b in some embodiments of this application. Figure 8This is a schematic diagram of the structure of the second fine gate x2a in some embodiments of this application. The second fine gate x2a includes a first fine gate portion x21 overlapping with the busbar 1200b, and a second fine gate portion x22 excluding the first fine gate portion x21. Along the direction from the second surface side 1102 to the first surface side 1101, the size of the second fine gate portion x22 is larger than the size of the first fine gate portion x21. In this case, the fine gate group 1112a on the second surface side 1102 is different from the fine gate group on the second surface side 1102 shown above.

[0094] For example, in conjunction with reference Figure 8 The second fine grating x22 has a third dimension h3 along the first direction F1, and the first fine grating x21 has a fourth dimension h4 along the first direction F1. The third dimension h3 is larger than the fourth dimension h4. In this way, the second fine grating x2a roughly forms a stepped portion.

[0095] In this way, by controlling the size of each part of the second fine gate x2a, not only can the thicker second fine gate part x22 be used to undertake the transmission task of higher current density, but also the risk of local temperature rise and electromigration caused by excessive current concentration at the junction of the fine gate 11121 and the bus 1200b can be reduced.

[0096] According to some embodiments of this application, please refer to Figure 9 , Figure 9 This is a partial structural diagram of the battery cell 1110b in some other embodiments of this application. The first portion P1b includes a middle portion P11 and two edge portions P12 located in the middle portion P11 along the arrangement direction of the fine grid 11121 in the fine grid group 1112b located on the second surface side 1102. That is, the two sides of the middle portion P11 along the second direction F2 are the edge portions P12. Along the direction from the second surface side 1102 to the first surface side 1101, the size of the middle portion P11 is smaller than the size of the edge portions P12. At this time, the fine grid group 1112b on the second surface side 1102 is different from the fine grid group on the second surface side 1102 shown above.

[0097] In this way, the thicker edge portions P12 on both sides of the middle portion P11 can be used to buffer stress and alleviate interface failure caused by thermal expansion and contraction and mechanical load. The thicker edge portions P12 on both sides can also be used to distribute the lamination pressure more evenly along the edges. The lower middle portion P11 can provide more deformation space for the busbar 1200, thereby further reducing the risk of microcracks in the cell 1110b during the lamination process.

[0098] According to some embodiments of this application, please refer to Figure 10 , Figure 10This is a partial structural schematic diagram of the battery cell 1110c in some embodiments of this application. From the middle portion P11a to the edge portion P12a, the size of the first portion P1c decreases linearly along the direction from the second surface side 1102 to the first surface side 1101. At this time, the fine grid group 1112c on the second surface side 1102 is different from the fine grid group on the second surface side 1102 shown above.

[0099] The linear decrease means that the dimension of the first part P1c along the first direction F1 decreases as a function of the spatial displacement from the middle part P11a to the edge part P12a, with no abrupt change in the rate of change of dimension. (Combined with...) Figure 10 As shown in the diagram, it can be seen that the dimensions of the fine grid 11121 in the first part P1c have changed along the first direction F1.

[0100] Thus, by further controlling the dimensions of the first part P1c, stress can be distributed more evenly while ensuring that the busbar 1200 can be placed in the corresponding position.

[0101] Based on some embodiments of this application, please continue to refer to Figure 9 In the fine grid 11121 of the first part P1b, the dimension of the previous fine grid 11121 in the direction from the middle part P11 to the edge part P12 in the direction from the second surface side 1102 to the first surface side 1101 is greater than the dimension of the subsequent fine grid 11121 in the direction from the second surface side 1102 to the first surface side 1101.

[0102] In this way, the ease of manufacturing the fine grid 11121 can be improved while ensuring a more uniform distribution of stress.

[0103] According to some embodiments of this application, in the fine grid of the first portion, at least a portion of the fine grid's surface facing the busbar includes at least one of an inclined plane, a straight plane, and a curved surface. The inclined plane intersects with but is not perpendicular to the direction of the second surface side 1102 pointing towards the first surface side 1101, and the straight plane is perpendicular to the direction of the second surface side 1102 pointing towards the first surface side 1101.

[0104] For example, with Figure 9 For example, in the fine grid 11121 of the first part P1b, the surface of the fine grid 11121 facing the busbar 1200 is a straight plane. This straight plane is perpendicular to the first direction F1. Figure 10 For example, in the fine grid 11121 of the first part P1c, the surface of the fine grid 11121 facing the busbar 1200 is an inclined plane. The inclined plane intersects the first direction F1 but is not perpendicular to it. Figure 11 For example, Figure 11This is a partial structural schematic diagram of the battery cell 1110d in some embodiments of this application. Figure 11 The diagram illustrates the fine grid 11121 in the first part P1d, where the surface of the fine grid 11121 facing the busbar 1200 is a straight plane. Figure 12 For example, Figure 12 This is a partial structural schematic diagram of the battery cell 1110e in some other embodiments of this application, illustrating that in the fine grid 11121 of the first part P1e, the surface of the fine grid 11121 facing the busbar 1200 is curved. Figure 13 For example, Figure 13 This is a partial structural schematic diagram of the battery cell 1110f in some other embodiments of this application, illustrating that in the fine grid 11121 of the first portion P1f, the surface of the fine grid 11121 facing the busbar 1200 is curved. Figure 12 and Figure 13 The shapes of the curved surfaces shown in the diagrams are different. Furthermore, in... Figure 12 The size of the middle part P11b of the first part P1e shown in the diagram along the first direction F1 is smaller than the size of the edge part P12b along the first direction F1.

[0105] It should be noted that, for the sake of clarity in illustrating the fine grid 11121, in Figures 9 to 13 The busbar is not shown in the diagram; however, it can be understood by referring to the other attached diagrams where the busbar is shown. Furthermore, Figure 11 The fine grating group 1112d shown in the figure Figure 12 The fine grating group 1112e shown in the figure and Figure 13 The fine grating group 1112f shown in the figure is different from the fine grating group shown above.

[0106] Thus, by controlling the shape of at least a portion of the fine grid 11121 facing the busbar in the first part, different stress dispersion effects can be achieved. For example, a straight surface can directly face the busbar, an inclined surface can utilize the advantage of dimensional variation to enhance the stress dispersion effect, and a curved surface can utilize its shape to enhance the stress dispersion effect. When these surfaces are freely combined, since different surfaces have different shapes, the differences between shapes can be used to break the stress transmission path, which is also more conducive to reducing the risk of microcracks during lamination.

[0107] According to some embodiments of this application, in the first portion of the fine grid 11121, at least a portion of the fine grid 11121 has a cross-sectional shape including at least one of rectangular, arc-shaped, and trapezoidal shapes. The cross-section of the fine grid 11121 is perpendicular to the longitudinal extension direction of the fine grid 11121.

[0108] The longitudinal extension direction of the fine grid 11121 is parallel to the third direction F3.

[0109] For example, with Figure 9 For example, the cross-sectional shape of the fine grid 11121 of the first part P1b is rectangular, to illustrate the case where the cross-sectional shape is rectangular. Figure 11 For example, the cross-sectional shape of the fine grid 11121 of the first part P1d is trapezoidal, to illustrate the case where the cross-sectional shape is trapezoidal. Figure 13 For example, the cross-sectional shape of the fine grid 11121 of the first part P1f is bow-shaped.

[0110] Thus, by controlling the cross-sectional shape of at least some of the fine grids 11121 in the first part, different stress dispersion effects can be achieved. For example, a trapezoidal shape can improve the stability of the fine grids 11121 while maintaining certain electrical connectivity, and the trapezoidal shape is also conducive to stress dispersion. An arc shape can utilize its curved surface to enhance the stress dispersion effect, while a rectangle provides a certain dispersion effect and is easy to manufacture. When these shapes are freely combined, the differences between the shapes can be used to break the stress transmission path, which is also more conducive to reducing the risk of microcracks during lamination.

[0111] Based on some embodiments of this application, please continue to refer to Figure 3 Along the direction from the second surface side 1102 to the first surface side 1101, the ratio of the size of the first part P1 to the size of the second part P2 is 0.5 to 0.8.

[0112] For example, with Figure 3 For example, the ratio of the first dimension h1 to the second dimension h2 is between 0.5 and 0.8. The ratio of the first dimension h1 to the second dimension h2 can be 0.5, 0.6, 0.7, 0.75, or 0.8. The ratio of the first dimension h1 to the second dimension h2 can be any value within the range of 0.5 to 0.8, and no specific restriction is imposed here.

[0113] It should be noted that when the fine grid 11121 in the first part P1 has multiple size specifications along the first direction F1, the ratio of the size of these multiple specifications to the size of the second part P2 is also in the range of 0.5 to 0.8.

[0114] Thus, by controlling the size ratio of the first part P1 and the second part P2, not only can different regions have a certain height difference, but the electrical connection performance of the fine grid 11121 can also be taken into account.

[0115] Based on some embodiments of this application, please continue to refer to Figure 3 Along the direction from the second surface side 1102 to the first surface side 1101, the difference between the size of the second part P2 and the size of the first part P1 is 2 micrometers to 5 micrometers.

[0116] For example, with Figure 3For example, the difference between the first dimension h1 and the second dimension h2 is 2 micrometers, 3 micrometers, 4 micrometers, 4.5 micrometers, or 5 micrometers. The difference between the first dimension h1 and the second dimension h2 can be any value within the range of 2 micrometers to 5 micrometers, and no specific restriction is imposed here.

[0117] Thus, by controlling the size difference between the first part P1 and the second part P2, not only can different regions have a certain height difference, but the electrical connection performance of the fine grid 11121 can also be taken into account.

[0118] According to some embodiments of this application, please refer to Figure 14 , Figure 14 This is a partial structural diagram of the battery cell 1110a and the busbar 1200c cooperating in some other embodiments of this application. Along the direction from the second surface side 1102 to the first surface side 1101, the first portion P1a has a protrusion P121 protruding towards the busbar 1200c, and the busbar 1200c has a recess 1202 located on the side of the busbar 1200c facing the first portion P1a. Along the direction from the second surface side 1102 to the first surface side 1101, the orthographic projection of the protrusion P121 lies within the orthographic projection range of the recess 1202.

[0119] The orthographic projection of the convex portion P121 lies within the orthographic projection range of the concave portion 1202; that is, from the perspective of the first direction F1, the convex portion P121 lies within the range of the concave portion 1202. The convex portion P121 and the concave portion 1202 overlap.

[0120] For example, with Figure 14 For example, the second fine grid x2a is shown with a protrusion P121, in conjunction with reference to... Figure 8 That is, the protrusion P121 is part of the second fine grating x22. Of course, the protrusion P121 can also be provided on the first fine grating x1, and there is no specific limitation here.

[0121] Thus, through such a concave-convex mating structure, the concave-convex mating interface can be used to alleviate thermal cycling shear stress and reduce the risk of microcracks and desoldering.

[0122] Based on some embodiments of this application, please continue to refer to Figure 2 In the battery string 1100, the outermost battery cell 1110 is the first battery cell 11101, and the battery cell 1110 adjacent to the first battery cell 11101 is the second battery cell 11102. The busbar 1200 includes an edge busbar 1210. The edge busbar 1210 is disposed on the first battery cell 11101; or, the edge busbar 1210 is disposed on the second battery cell 11102.

[0123] For example, with Figure 2For example, the edge busbar 1210 is shown when it is located on the first battery cell 11101. Of course, the edge busbar 1210 can also be located on the second battery cell 11102, and there is no specific limitation here.

[0124] Thus, since the first solar cell 11101 is an edge solar cell 1110 and the second solar cell 11102 is a solar cell 1110 near the edge, placing the edge busbar 1210 on either the first solar cell 11101 or the second solar cell 11102 not only shortens the outer current transmission path, reduces series resistance, and improves busbar efficiency, but also strengthens the structural connection on the outside of the cell string 1100, disperses mechanical stress during encapsulation or use, and simplifies the overall wiring process. Placing the edge busbar 1210 on the first solar cell 11101 further shortens the current transmission path and improves failure resistance. Placing the edge busbar 1210 on the second solar cell 11102 improves the fault tolerance of the cell string 1100, reduces the risk of interference between the busbar 1200 and the module edge, and is beneficial for photovoltaic module encapsulation. Furthermore, combined with the height difference control of the first and second parts illustrated above, it further improves the structural reliability at the edge busbar 1210.

[0125] Based on some embodiments of this application, please continue to refer to Figure 2 The edge busbar 1210 is located in the middle of the battery cell 1110 where the edge busbar 1210 is located; or, the edge busbar 1210 is located at the edge of the battery cell 1110 where the edge busbar 1210 is located.

[0126] For example, with Figure 2 For example, the edge busbar 1210 is shown in the case where it is located in the middle of the first battery cell 11101. Of course, the edge busbar 1210 can also be located at the edge of the first battery cell 11101. When the edge busbar 1210 is located in the second battery cell 11102, it can be in the middle or at the edge, and there is no specific limitation here.

[0127] Thus, by placing the edge busbar 1210 at the center of the solar cell 1110 where it is located, not only can the series resistance within a single cell be reduced, but the overall structural stability can also be improved. Furthermore, placing the edge busbar 1210 at the edge of the solar cell 1110 facilitates reinforcement of the edge area and enhances the timeliness of fault isolation.

[0128] Based on some embodiments of this application, please continue to refer to Figure 2In the battery string 1100, the battery cell 1110 located in the middle position is the third battery cell 11103. The busbar 1200 includes an intermediate busbar 1220 disposed on the third battery cell 11103. The intermediate busbar 1220 is located in the middle position of the third battery cell 11103; or, the intermediate busbar 1220 is located at the edge position of the third battery cell 11103.

[0129] When the number of battery cells 1110 in the battery string 1100 is odd, there is one third battery cell 11103. When the number of battery cells 1110 in the battery string 1100 is even, there are two third battery cells 11103. When there are two third battery cells 11103, the intermediate busbar 1220 is located on one of the third battery cells 11103.

[0130] For example, with Figure 2 For example, the diagram illustrates the case where the intermediate busbar 1220 is located in the middle of the third battery cell 11103. Of course, the intermediate busbar 1220 can also be located at the edge of the third battery cell 11103. No specific limitation is made here.

[0131] Thus, by placing the intermediate busbar 1220 in the middle of the third battery cell 11103, it not only helps to reduce the series resistance but also helps to improve the structural support in the middle of the battery string 1100 and disperse the stress throughout the string. By placing the intermediate busbar 1220 at the edge of the third battery cell 11103, and in conjunction with the aforementioned height difference between the first part P1 and the second part P2, it also helps to weaken the stress superposition of the busbar 1200 on the third battery cell 11103.

[0132] According to some embodiments of this application, please refer to Figures 15 to 17 , Figure 15 This is a partial structural diagram showing the interaction between the battery string 1100a, the busbar 1200, and the electrical connector 1300 in some embodiments of this application. Figure 16 This is a partial structural diagram of the battery cell 1110' and electrical connector 1300 in some embodiments of this application. Figure 17This is a partial structural diagram illustrating the interaction of the solar cell 1110', electrical connector 1300, and busbar 1200 in some embodiments of this application. The solar cell 1110' is a back-contact solar cell. The photovoltaic module also includes an electrical connector 1300 located on the second surface side 1102. The solar cells 1110' in the battery string 1100a are connected through the electrical connector 1300. The electrical connector 1300 includes a first electrical connector 1300a and a second electrical connector 1300b, which are alternately arranged at intervals along a first direction F1 on the solar cells 1110'. The busbar 1200 is electrically connected to the first electrical connector 1300a and insulated from the second electrical connector 1300b. Wherein, in Figure 16 The location of bus 1200 is indicated by a dashed line.

[0133] Electrical connector 1300 is a conductive connector that contacts the battery cell on the second surface side 1102. For example, electrical connector 1300 can be a solder strip. The polarity of the grid 11121 connected to the first electrical connector 1300a is different from the polarity of the grid 11121 connected to the second electrical connector 1300b.

[0134] Thus, by applying the height difference between the first part P1 and the second part P2 mentioned above to the back-contact solar cell and placing the busbar 1200 on the second surface side 1102, not only can the space for the protruding head and tail electrical connectors 1300 be saved and the manufacturing cost of the electrical connection be reduced, but the risk of microcracks can also be reduced. In addition, by saving the space for the protruding head and tail electrical connectors 1300, it is beneficial to increase the area of ​​the solar cell 1110', thereby increasing the power of the module per unit area.

[0135] According to some embodiments of this application, please refer to Figures 18 to 21 , Figure 18 This is a partial structural diagram showing the interaction between the battery cell 1110, the first electrical connector 1300a, and the busbar 1200 in some embodiments of this application. Figure 19 This is a schematic diagram of the structure of the first electrical connector 1300a in some embodiments of this application. Figure 20 This is a partial structural diagram showing the interaction between the battery cell 1110, the second electrical connector 1300b, and the busbar 1200 in some embodiments of this application. Figure 21The diagram below shows the structure of the second electrical connector 1300b in some embodiments of this application. The first electrical connector 1300a includes a first electrical connection portion 1311 that overlaps with the busbar 1200, and a second electrical connection portion 1312 other than the first electrical connection portion 1311. The first electrical connection portion 1311 is recessed relative to the second electrical connection portion 1312 and is closer to the battery cell 1110. And / or, the second electrical connector 1300b includes a third electrical connection portion 1321 that overlaps with the busbar 1200, and a fourth electrical connection portion 1322 other than the third electrical connection portion 1321. The third electrical connection portion 1321 is recessed relative to the fourth electrical connection portion 1322 and is closer to the battery cell 1110.

[0136] The first electrical connection portion 1311 and the second electrical connection portion 1312 can be integrally formed or fixedly connected. The third electrical connection portion 1321 and the fourth electrical connection portion 1322 can be integrally formed or fixedly connected. No specific restrictions are imposed here.

[0137] The first electrical connection 1311 overlaps with the busbar 1200, meaning that from the perspective of the first direction F1, the first electrical connection 1311 and the busbar 1200 are opposite each other. The second electrical connection 1312 does not overlap with the busbar 1200, meaning that from the perspective of the first direction F1, the second electrical connection 1312 and the busbar 1200 are not opposite each other. The third electrical connection 1321 and the fourth electrical connection 1322 can be understood with reference to the foregoing, and will not be described again here.

[0138] Thus, by recessing the portion of the first electrical connector 1300a opposite to the busbar 1200, and / or recessing the portion of the second electrical connector 1300b opposite to the busbar 1200, it is beneficial to further reduce the height difference between different areas of the battery string 1100, thereby further improving flatness and further reducing the risk of microcracks. Furthermore, the recessed portion also increases the connection area of ​​the electrical connector 1300, thereby improving the reliability of the electrical connection.

[0139] According to some embodiments of this application, please refer to Figure 22 and Figure 23 , Figure 22 This is a schematic diagram showing the structure of the battery cell 1110', electrical connector 1300, busbar 1200 and first insulating member 1400 cooperating with each other in some embodiments of this application. Figure 23The diagram below illustrates the structure of the first insulating member 1400 in some embodiments of this application. The photovoltaic module further includes the first insulating member 1400, which is disposed on the side of the second electrical connector 1300b facing away from the solar cell 1110'. The busbar 1200 is insulated from the second electrical connector 1300b by means of the first insulating member 1400. The first insulating member 1400 includes a first insulating portion 1410 overlapping with the busbar 1200, and a second insulating portion 1420 excluding the first insulating portion 1410. The first insulating portion 1410 is recessed compared to the second insulating portion 1420 and is closer to the solar cell 1110'.

[0140] The first insulating element 1400 is a component with insulating properties. Exemplarily, the first insulating element 1400 can be a multilayer structure. The outermost layer can be made of EVA (Ethylene Vinyl Acetate Copolymer), or a three-layer co-extruded structure of EVA-POE-EVA, or PO (Polyolefin). The middle layer can be made of PET. Of course, the insulating element can also be a single-layer structure; no specific limitation is made here. Here, POE stands for Polyolefin Elastomer.

[0141] The first insulating portion 1410 overlaps with the busbar 1200, meaning that from the perspective of the first direction F1, the first insulating portion 1410 and the busbar 1200 are opposite each other. The second insulating portion 1420 does not overlap with the busbar 1200, meaning that from the perspective of the first direction F1, the second insulating portion 1420 and the busbar 1200 are not opposite each other.

[0142] Thus, by recessing the portion of the first insulating member 1400 opposite to the busbar 1200, it is beneficial to further reduce the height difference between different areas of the battery string 1100, thereby further improving flatness and further reducing the risk of microcracks. In addition, the recessed portion also facilitates the positioning of the busbar 1200.

[0143] According to some embodiments of this application, please refer to Figure 24 , Figure 24 This is a partial structural diagram illustrating the interaction between the solar cell 1110'', electrical connector 1300, and busbar 1200 in other embodiments of this application. The solar cell 1110'' is a tunneling oxide passivated contact solar cell. The photovoltaic module also includes the electrical connector 1300, through which the solar cells 1110'' in the cell string are connected, and the busbar 1200 is electrically connected to the electrical connector 1300. Figure 24 The fine grid 11121' shown in the diagram is a grid line of the same polarity. This is different from the back contact cell mentioned above.

[0144] Thus, by applying the height difference between the first and second parts mentioned above to the tunnel oxide passivated contact cell, and by placing the busbar 1200 on the second surface side 1102, not only can the space for the head and tail electrical connectors 1300 to extend be saved and the manufacturing cost of the electrical connections be reduced, but the risk of microcracks can also be reduced. Furthermore, by saving the space for the head and tail electrical connectors 1300 to extend, it is beneficial to increase the area of ​​the cell 1110'', thereby increasing the power of the module per unit area.

[0145] Based on some embodiments of this application, please continue to refer to Figure 24 and in conjunction with reference Figure 25 , Figure 25 This is a partial structural diagram illustrating the interaction between adjacent battery cells 1110'', the first busbar 1230, and the third electrical connector 1300c in some embodiments of this application. The busbar 1200 includes the first busbar 1230, and the third electrical connector 1300 is electrically connected to the first busbar 1230. The third electrical connector 1300c includes a main body 1310 located on the first surface side 1101 and a bent portion 1320 connected to the main body 1310. The bent portion 1320 is electrically connected to the first busbar 1230, and the first busbar 1230 is insulated from the electrical connector 1300 located on the second surface side 1102.

[0146] Thus, by configuring the third electrical connector 1300c to include a main body portion 1310 and a bent portion 1320, it is advantageous to connect the third electrical connector 1300c to the first busbar 1230 located on the second surface side 1102.

[0147] According to some embodiments of this application, please refer to Figure 26 , Figure 26 This is an exploded structural diagram showing the interaction between the first busbar 1230 and the second insulator 1500 in some embodiments of this application. The photovoltaic module also includes the second insulator 1500, which is disposed on the side of the electrical connector 1300 located on the second surface side 1102 away from the solar cell. The first busbar 1230 is insulated from the second surface side 1102 by means of the second insulator 1500. The second insulator 1500 includes a third insulating portion 1510 overlapping with the first busbar 1230, and a fourth insulating portion 1520 other than the third insulating portion 1510. The third insulating portion 1510 is recessed compared to the fourth insulating portion 1520 and is closer to the solar cell. Figure 26 In order to facilitate the illustration of the structure of the second insulating element 1500, the first busbar 1230 and the second insulating element 1500 are disassembled.

[0148] The third insulating portion 1510 overlaps with the first busbar 1230, meaning that from the perspective of the first direction F1, the third insulating portion 1510 and the first busbar 1230 are opposite each other. The fourth insulating portion 1520 does not overlap with the first busbar 1230, meaning that from the perspective of the first direction F1, the fourth insulating portion 1520 and the first busbar 1230 are not opposite each other.

[0149] Thus, by recessing the portion of the second insulator 1500 opposite to the first busbar 1230, it is beneficial to further reduce the height difference between different areas of the battery string, thereby further improving flatness and further reducing the risk of microcracks. In addition, the recessed portion also facilitates the positioning of the first busbar 1230.

[0150] Based on some embodiments of this application, please continue to refer to Figure 1 The photovoltaic module 1000 also includes an encapsulation layer 1700 and a cover plate 1600. The encapsulation layer 1700 is used to cover the surface of the cell string 1100, and the cover plate 1600 is used to cover the surface of the encapsulation layer 1700 away from the cell string 1100.

[0151] Furthermore, the battery cells 1110 are electrically connected in whole or in multiple segments to form multiple battery strings 1100, and the multiple battery strings 1100 are electrically connected in series and / or in parallel.

[0152] In some embodiments, the encapsulation layer 1700 covers both the front and back sides of the solar cell.

[0153] In some embodiments, the encapsulation layer 1700 may be an organic encapsulation film such as ethylene-vinyl acetate copolymer (EVA) film, polyethylene octene coelastomer (POE) film, or polyethylene terephthalate (PET) film.

[0154] In some embodiments, the cover plate 1600 can be a glass cover plate, a plastic cover plate, or other cover plate with light-transmitting function.

[0155] In some embodiments, the surface of the cover plate 1600 facing the encapsulation layer 1700 can be an uneven surface, thereby increasing the utilization of incident light.

[0156] It should be noted that in the above-illustrated figures, some structures have been omitted for the purpose of illustrating the corresponding embodiments, and should be understood as not being a limitation on the structure of the embodiments of this application.

[0157] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0158] The embodiments described above are merely illustrative of several implementation methods of this application, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the patent application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the protection scope of this application. Therefore, the protection scope of this patent application should be determined by the appended claims.

Claims

1. A photovoltaic module, characterized in that, include: Multiple battery strings, each battery string having a first surface side and a second surface side disposed opposite to each other, each battery string comprising multiple battery cells connected in series, each battery cell comprising a fine grid group, the fine grid group being located at least on the second surface side; and A busbar is located on the second surface side and is electrically connected to the plurality of batteries in series; The fine grid group includes a first portion that overlaps with the busbar, and a second portion other than the first portion; Along the direction from the second surface side to the first surface side, the size of the first portion is smaller than the size of the second portion.

2. The photovoltaic module according to claim 1, characterized in that, The first portion includes multiple fine grids in the fine grid group located on the second surface side.

3. The photovoltaic module according to claim 2, characterized in that, The busbar has a groove on the side facing the plurality of battery strings; Along the direction from the second surface side to the first surface side, the orthographic projection of the first portion lies within the orthographic projection range of the groove.

4. The photovoltaic module according to claim 1, characterized in that, The first portion includes a plurality of fine grids in the fine grid group located on the second surface side, and a portion of at least one fine grid in the fine grid group located on the second surface side; The fine gate in the fine gate group located on the second surface side is the first fine gate, and the fine gate in at least one fine gate in the fine gate group located on the second surface side is the second fine gate; In the first part, along the arrangement direction of the fine grids located on the second surface side, at least one of the first fine grid and the last fine grid is the second fine grid, and the remaining fine grids are the first fine grids.

5. The photovoltaic module according to claim 4, characterized in that, The second fine gate includes a first fine gate portion that overlaps with the busbar, and a second fine gate portion other than the first fine gate portion; Along the direction from the second surface side to the first surface side, the size of the second fine grid portion is larger than the size of the first fine grid portion.

6. The photovoltaic module according to any one of claims 1-5, characterized in that, The first part includes a middle portion and two edge portions located in the middle portion along the grid arrangement direction in the grid group located on the second surface side; Along the direction from the second surface side to the first surface side, the size of the middle portion is smaller than the size of the edge portion.

7. The photovoltaic module according to claim 6, characterized in that, The dimension of the first portion decreases linearly from the middle portion toward the edge portion in the direction from the second surface side toward the first surface side.

8. The photovoltaic module according to claim 6, characterized in that, In the first portion of the fine grid, the dimension of the preceding fine grid in the direction from the middle portion to the edge portion along the second surface side to the first surface side is greater than the dimension of the following fine grid in the direction from the second surface side to the first surface side.

9. The photovoltaic module according to any one of claims 1-5, characterized in that, In the first portion of the fine grid, at least a portion of the surface of the fine grid facing the busbar includes at least one of an inclined plane, a straight plane, and a curved surface; The inclined plane intersects the direction of the second surface side pointing towards the first surface side but is not perpendicular to it, and the straight plane is perpendicular to the direction of the second surface side pointing towards the first surface side.

10. The photovoltaic module according to any one of claims 1-5, characterized in that, In the first part of the fine grid, at least a portion of the cross-sectional shape of the fine grid includes at least one of rectangular, arc-shaped, and trapezoidal shapes; The cross-section of the fine grid is perpendicular to the longitudinal extension direction of the fine grid.

11. The photovoltaic module according to any one of claims 1-5, characterized in that, Along the direction from the second surface side to the first surface side, the ratio of the size of the first portion to the size of the second portion is 0.5 to 0.

8.

12. The photovoltaic module according to any one of claims 1-5, characterized in that, Along the direction from the second surface side to the first surface side, the difference between the size of the second portion and the size of the first portion is 2 micrometers to 5 micrometers.

13. The photovoltaic module according to any one of claims 1-5, characterized in that, Along the direction from the second surface side to the first surface side, the first portion has a protrusion protruding toward the manifold, and the manifold has a recess located on the side of the manifold facing the first portion; Along the direction from the second surface side to the first surface side, the orthogonal projection of the convex portion lies within the orthogonal projection range of the concave portion.

14. The photovoltaic module according to any one of claims 1-5, characterized in that, In the battery string, the outermost battery cell is the first battery cell, and the battery cell adjacent to the first battery cell is the second battery cell; the busbar includes an edge busbar; Wherein, the edge busbar is disposed on the first battery cell; or The edge busbar is located on the second battery cell.

15. The photovoltaic module according to claim 14, characterized in that, The edge busbar is located in the middle of the battery cell where the edge busbar is located; or The edge busbar is located at the edge of the battery cell where the edge busbar is located.

16. The photovoltaic module according to any one of claims 1-5, characterized in that, In the battery string, the battery cell located in the middle position is the third battery cell; the busbar includes an intermediate busbar disposed on the third battery cell; Wherein, the intermediate busbar is located in the middle of the third battery cell; or The intermediate busbar is located at the edge of the third battery cell.

17. The photovoltaic module according to any one of claims 1-5, characterized in that, The battery cell is a back-contact battery cell; The photovoltaic module further includes an electrical connector located on the second surface side, and the cells in the battery string are connected through the electrical connector. The electrical connector includes a first electrical connector and a second electrical connector, and the first electrical connector and the second electrical connector are alternately spaced on the battery cells along a first direction. The busbar is electrically connected to the first electrical connector and is insulated from the second electrical connector.

18. The photovoltaic module according to claim 17, characterized in that, The first electrical connector includes a first electrical connection portion overlapping the busbar, and a second electrical connection portion other than the first electrical connection portion; the first electrical connection portion is recessed relative to the second electrical connection portion and is closer to the battery cell; and / or The second electrical connector includes a third electrical connection portion that overlaps with the busbar, and a fourth electrical connection portion other than the third electrical connection portion; the third electrical connection portion is recessed compared to the fourth electrical connection portion and is closer to the battery cell.

19. The photovoltaic module according to claim 17, characterized in that, The photovoltaic module further includes a first insulating member, which is disposed on the side of the second electrical connector away from the solar cell, and the busbar is insulated from the second electrical connector by means of the first insulating member; The first insulating member includes a first insulating portion that overlaps with the busbar and a second insulating portion other than the first insulating portion; the first insulating portion is recessed relative to the second insulating portion and is closer to the battery cell.

20. The photovoltaic module according to any one of claims 1-5, characterized in that, The battery cell is a tunnel oxide passivated contact battery cell; The photovoltaic module also includes an electrical connector, through which the cells in the battery string are connected, and the busbar is electrically connected to the electrical connector.

21. The photovoltaic module according to claim 20, characterized in that, The busbar includes a first busbar, and the electrical connector electrically connected to the first busbar is a third electrical connector; The third electrical connector includes a main body portion located on the first surface side and a bent portion connected to the main body portion; the bent portion is electrically connected to the first busbar, and the first busbar is insulated from the electrical connector located on the second surface side.

22. The photovoltaic module according to claim 21, characterized in that, The photovoltaic module further includes a second insulating member, which is disposed on the side of the electrical connector located on the second surface side away from the solar cell, and the first busbar is insulated from the second surface side by means of the second insulating member; The second insulating member includes a third insulating portion that overlaps with the first busbar, and a fourth insulating portion other than the third insulating portion; the third insulating portion is recessed compared to the fourth insulating portion and is closer to the battery cell.

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