A back-contact battery, a battery module, and a photovoltaic system

Abstract

The present application is applicable to the technical field of solar cell, and provides a back-contact battery, a battery module and a photovoltaic system. The back-contact battery includes a silicon substrate, a plurality of first-polarity fine grids and a plurality of second-polarity fine grids; the silicon substrate includes a silicon substrate and a plurality of passivated contact structures disposed on the silicon substrate; the first-polarity fine grids and the second-polarity fine grids are spaced apart and disposed on the silicon substrate, arranged along a first direction, and at least one of them is electrically connected to the passivated contact structure; the first-polarity fine grid includes a first grid line, the first grid line is provided with a first connection block, the width of the first connection block is greater than the width of the first grid line, and the length of the first connection block is greater than or equal to 100 μm; the second-polarity fine grid includes a second grid line, the second grid line includes a first main body portion and a first bending portion connected to each other, the first main body portion extends along a second direction, the second direction intersects with the first direction, the first bending portion is correspondingly arranged with the first connection block, and bends away from the first connection block from the first main body portion.

Description

Technical Field

[0001] This application belongs to the technical field of solar cells, and particularly relates to a back-contact battery, a battery module, and a photovoltaic system. Background Art

[0002] Solar cell power generation is a sustainable clean energy source, which can convert sunlight into electrical energy by utilizing the photovoltaic effect of the semiconductor p-n junction. In related technologies, electrical connection components such as solder tapes are usually used to connect back-contact batteries to form a battery string. However, the electrical connection components are prone to falling off from the back-contact batteries, resulting in poor connection stability.

[0003] Based on this, how to improve the connection stability between the back-contact battery and the electrical connection component has become an urgent problem to be solved. Summary of the Invention

[0004] This application provides a back-contact battery, a battery module, and a photovoltaic system, aiming to solve the problem of how to improve the connection stability between the back-contact battery and the electrical connection component.

[0005] The back-contact battery provided by this application includes:

[0006] A silicon substrate, including a silicon substrate and a plurality of passivated contact structures provided on the silicon substrate;

[0007] A plurality of first-polarity fine grids and a plurality of second-polarity fine grids, provided on the silicon substrate and arranged along a first direction, the first-polarity fine grids and the second-polarity fine grids being spaced apart; at least one of the first-polarity fine grids and the second-polarity fine grids is electrically connected to the passivated contact structures;

[0008] The first-polarity fine grid includes a first grid line, the first grid line is provided with a first connection block, the width of the first connection block is greater than the width of the first grid line, and the length of the first connection block is greater than or equal to 100 μm;

[0009] The second-polarity fine grid includes a second grid line, the second grid line includes a connected first main body portion and a first bent portion, the first main body portion extends along a second direction, the second direction intersects with the first direction, and the first bent portion is correspondingly arranged with the first connection block and bends away from the first connection block from the first main body portion.

[0010] The battery module provided by this application includes the back-contact battery according to any one of the above.

[0011] The photovoltaic system provided by this application includes the battery module according to any one of the above.

[0012] The back-contact battery, battery module, and photovoltaic system according to the embodiments of the present application. Since the width of the first connection block is greater than the width of the first grid line and the length is greater than or equal to 100 μm, the contact area between the first connection block and the electrical connection member can be increased, the pulling force can be increased, the risk of the electrical connection member falling off from the back-contact battery can be reduced, and the connection stability between the back-contact battery and the electrical connection member can be improved. At the same time, since the first bending portion in the second grid line bends away from the first connection block from the first main body portion, more space can be provided for the first connection block with a larger width, facilitating the widening of the first connection block, and the short-circuit risk caused by too small an electrode spacing between two polarities can be reduced. Moreover, since at least one of the first-polarity fine grid and the second-polarity fine grid is electrically connected to the passivation contact structure provided on the silicon substrate, recombination can be reduced, which is beneficial to improving the photoelectric conversion efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 is a schematic diagram of a partial structure of a back-contact battery according to an embodiment of the present application;

[0014] Figure 2 is Figure 1 partial structure schematic diagram of the back-contact battery at the A range;

[0015] Figure 3 is a schematic diagram of the structure of a back-contact battery according to an embodiment of the present application;

[0016] Figure 4 is a back-contact battery according to another embodiment of the present application and Figure 1 partial structure schematic diagram of the corresponding part at the A range;

[0017] Figure 5 is a back-contact battery according to another embodiment of the present application and Figure 1 partial structure schematic diagram of the corresponding part at the A range;

[0018] Figure 6 is a back-contact battery according to another embodiment of the present application and Figure 1 partial structure schematic diagram of the corresponding part at the A range;

[0019] Figure 7 is a schematic diagram of a partial structure of a back-contact battery according to an embodiment of the present application;

[0020] Figure 8 is Figure 7 partial structure schematic diagram of the back-contact battery at the B range;

[0021] Figure 9 is a back-contact battery according to another embodiment of the present application and Figure 7 partial structure schematic diagram of the corresponding part at the B range;

[0022] Figure 10is a partial structural schematic diagram of the back-contact battery of another embodiment of the present application and Figure 7 the corresponding part in the B range in

[0023] Figure 11 is a partial structural schematic diagram of the back-contact battery of another embodiment of the present application and Figure 7 the corresponding part in the B range in

[0024] Figure 12 is a partial structural schematic diagram of the back-contact battery of another embodiment of the present application and Figure 1 the corresponding part in the A range in

[0025] Figure 13 is a partial structural schematic diagram of the back-contact battery of another embodiment of the present application and Figure 1 the corresponding part in the A range in

[0026] Figure 14 is a partial structural schematic diagram of the back-contact battery of another embodiment of the present application and Figure 1 the corresponding part in the A range in

[0027] Figure 15 is a partial structural schematic diagram of the back-contact battery of another embodiment of the present application and Figure 1 the corresponding part in the A range in

[0028] Figure 16 is a partial structural schematic diagram of the back-contact battery of another embodiment of the present application and Figure 1 the corresponding part in the A range in

[0029] Figure 17 is a partial structural schematic diagram of the back-contact battery of another embodiment of the present application and Figure 1 the corresponding part in the A range in

[0030] Figure 18 is a partial structural schematic diagram of the back-contact battery of another embodiment of the present application and Figure 1 the corresponding part in the A range in

[0031] Figure 19 is a partial structural schematic diagram of the back-contact battery of another embodiment of the present application and Figure 7 the corresponding part in the B range in

[0032] Figure 20 is a partial structural schematic diagram of the back-contact battery of another embodiment of the present application and Figure 7 the corresponding part in the B range in

[0033] Figure 21 is a schematic diagram of the partial structure of the back-contact battery of an embodiment of the present application;

[0034] Figure 22 isFigure 21 Partial structural schematic diagram at the C range in the back-contact battery;

[0035] Figure 23 is the back-contact battery of another embodiment of the present application and Figure 21 partial structural schematic diagram at the corresponding position in the C range;

[0036] Figure 24 is the back-contact battery of another embodiment of the present application and Figure 21 partial structural schematic diagram at the corresponding position in the C range;

[0037] Figure 25 is the back-contact battery of another embodiment of the present application and Figure 21 partial structural schematic diagram at the corresponding position in the C range;

[0038] Figure 26 is a schematic diagram of the back-contact battery of an embodiment of the present application;

[0039] Figure 27 is Figure 26 schematic diagram of the partial structure of the back-contact battery. Detailed implementation manners

[0040] In order to make the objectives, technical solutions and advantages of the present application clearer, the present application will be further described in detail below with reference to the accompanying drawings and embodiments. Examples of the embodiments are shown in the drawings, where the same or similar reference numerals denote the same or similar elements or elements with the same or similar functions from beginning to end. The embodiments described below by referring to the drawings are exemplary only for explaining the present application and should not be construed as limiting the present application. In addition, it should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the present application.

[0041] In the description of the present application, it should be understood that the orientation or positional relationship indicated by the terms "length", "width", "upper", "lower", "left", "right", "horizontal", "top", "bottom", etc. is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the present application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus should not be construed as limiting the present application.

[0042] In addition, the terms "first" and "second" are only used for descriptive purposes and should not be construed as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include one or more of the described features. In the description of the present application, "a plurality" means two or more unless otherwise specifically defined.

[0043] In the description of the present application, it should be noted that unless otherwise clearly specified and defined, the terms "installed", "connected", and "coupled" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection, an electrical connection, or a connection that allows for mutual communication; it can be a direct connection, or an indirect connection through an intermediate medium, and can be the internal connection of two components or the interaction relationship between two components. For those of ordinary skill in the art, the specific meanings of the above terms in the present application can be understood according to specific circumstances.

[0044] In the present application, unless otherwise clearly specified and defined, the first feature being "on" or "under" the second feature may include the direct contact between the first and second features, or may include the situation where the first and second features are not in direct contact but in contact through additional features therebetween. Moreover, the first feature being "above", "over", and "on top of" the second feature includes the first feature being directly above and obliquely above the second feature, or merely indicating that the horizontal height of the first feature is higher than that of the second feature. The first feature being "under", "beneath", and "underneath" the second feature includes the first feature being directly below and obliquely below the second feature, or merely indicating that the horizontal height of the first feature is lower than that of the second feature.

[0045] The following disclosure provides many different embodiments or examples for implementing different structures of the present application. To simplify the disclosure of the present application, the components and settings of specific examples are described below. Of course, they are merely examples and are not intended to limit the present application. In addition, the present application may repeat reference numerals and / or reference letters in different examples, and this repetition is for the purpose of simplification and clarity, and does not itself indicate the relationship between the various embodiments and / or settings discussed. Furthermore, the present application provides examples of various specific processes and materials, but those of ordinary skill in the art can be aware of the application of other processes and / or the use scenarios of other materials.

[0046] Please refer to Figure 1 、 Figure 2 and Figure 3 , the back-contact battery 10 of the embodiment of the present application includes:

[0047] A silicon substrate 101, including a silicon wafer and a plurality of passivation contact structures disposed on the silicon wafer;

[0048] A plurality of first-polarity fine grids 11 and a plurality of second-polarity fine grids 12, disposed on the silicon substrate 101 and arranged along a first direction, with the first-polarity fine grids 11 and the second-polarity fine grids 12 spaced apart; at least one of the first-polarity fine grids 11 and the second-polarity fine grids 12 is electrically connected to the passivation contact structure;

[0049] The first-polarity fine grid 11 includes a first grid line 111, the first grid line 111 is provided with a first connection block 112, the width w1 of the first connection block 112 is greater than the width w2 of the first grid line 111, and the length s1 of the first connection block 112 is greater than or equal to 100 μm;

[0050] The second-polarity fine grid 12 includes a second grid line 121, the second grid line 121 includes a connected first main body portion 1211 and a first bent portion 1212, the first main body portion 1211 extends along a second direction, the second direction intersects with the first direction, the first bent portion 1212 is correspondingly arranged with the first connection block 112, and bends away from the first connection block 112 from the first main body portion 1211.

[0051] In the back-contact battery 10 of the embodiment of the present application, since the width w1 of the first connection block 112 is greater than the width w2 of the first grid line 111 and the length s1 is greater than or equal to 100 μm, the contact area between the first connection block 112 and the electrical connector can be increased, the pulling force can be increased, the risk of the electrical connector falling off from the back-contact battery 10 can be reduced, and the connection stability between the back-contact battery 10 and the electrical connector can be improved. At the same time, since the first bent portion 1212 in the second grid line 121 bends away from the first connection block 112 from the first main body portion 1211, more space can be provided for the first connection block 112 with a larger width, which is convenient for widening the first connection block 112, and the short-circuit risk caused by too small electrode spacing between the two polarities can be reduced. Moreover, since at least one of the first-polarity fine grid 11 and the second-polarity fine grid 12 is electrically connected to the passivation contact structure provided on the silicon substrate, recombination can be reduced, which is beneficial to improving the photoelectric conversion efficiency.

[0052] Specifically, the back-contact battery 10 may be a sliced battery formed by slicing a whole battery. For example, Figure 3 is a half-cell battery formed by cutting a whole battery in half. The back-contact battery 10 may also be an un-sliced whole battery. The whole back-contact battery 10 may include a slicing groove, and the whole battery can be cut along the slicing groove to obtain Figure 3 the sliced battery shown. The whole back-contact battery 10 may be asymmetric along the slicing groove or symmetric along the slicing groove.

[0053] In this article, the back-contact battery 10 without a main grid is taken as an example for explanation and illustration. It can be understood that the back-contact battery 10 may be a back-contact battery 10 with a main grid. In the case where the back-contact battery 10 is a back-contact battery 10 with a main grid, the main grid may be located in an area other than the first connection block 112. In this way, the connection between the main grid and the first connection block 112 and the first electrical connector can be prevented from being interfered.

[0054] Specifically, the silicon substrate 101 may include a silicon substrate, a first-polarity doping layer, a second-polarity doping layer, and a dielectric film layer 1003.

[0055] Further, the silicon substrate can be a P-type silicon substrate or an N-type silicon substrate; it can be a single-crystalline silicon substrate or a polycrystalline silicon substrate. The specific form of the silicon substrate is not limited herein.

[0056] Further, the first polar doping layer and the second polar doping layer are disposed on the silicon substrate. The doping polarities of the first polar doping layer and the second polar doping layer are different. The two doping layers can be formed by diffusing into the silicon substrate or by depositing a film layer on the silicon substrate.

[0057] It can be understood that in the thickness direction of the back-contact battery 10, the first polar doping layer is stacked on the silicon substrate, and the second polar doping layer is stacked on the silicon substrate. In the plane perpendicular to the thickness direction of the back-contact battery 10, the first polar doping layer and the second polar doping layer are distributed in regions, corresponding to the first polar doping region 13 and the second polar doping region 14 respectively, as Figures 12 - 20 shown.

[0058] The following statements "the first polar doping region 13 includes the first doping region 131" and "the first polar doping region 13 includes the third doping region 132" mean that the first doping region 131 and the third doping region 132 are doping regions of the first polarity. The following statements "the second polar doping region 14 includes the second doping region 141" and "the second polar doping region 14 includes the fourth doping region 142" mean that the second doping region 141 and the fourth doping region 142 are doping regions of the second polarity.

[0059] Further, the dielectric film layer 1003 can cover the first polar doping layer and the second polar doping layer. The first polar fine grid 11 passes through the dielectric film layer 1003 to contact the first polar doping layer, and the second polar fine grid 12 passes through the dielectric film layer 1003 to contact the second polar doping layer. Thus, the dielectric film layer 1003 is used to achieve electrical isolation between the first polar doping layer and the second polar doping layer, and at the same time, the dielectric film layer 1003 can be used to reduce light reflection and recombination. The dielectric film layer 1003 can also be disposed between at least a pair of adjacent first polar doping regions 13 and second polar doping regions 14 to electrically isolate the first polar doping region 13 and the second polar doping region 14. Note that for better display of the first polar doping region 13 and the second polar doping region 14, Figures 12 - 20 the part where the dielectric film layer 1003 covers the first polar doping region 13 and the second polar doping region 14 is omitted.

[0060] Specifically, the first polar fine grid 11 and the second polar fine grid 12 can be distributed in all regions of the silicon substrate 101; the first polar fine grid 11 and the second polar fine grid 12 can be distributed in part of the regions of the silicon substrate 101. It can be understood that in the regions of the silicon substrate 101 where the first polar fine grid 11 and the second polar fine grid 12 are not distributed, other fine grids can be distributed, main grids can be distributed, or grid lines can be not provided.

[0061] Specifically, the first polarity fine gate 11 and the second polarity fine gate 12 have different polarities. The first polarity fine gate 11 corresponds to the first polarity doping layer and the first polarity doping region 13. The second polarity fine gate 12 corresponds to the second polarity doping layer and the second polarity doping region 14.

[0062] Specifically, the number of the first polarity fine grids 11 may be 1, 2, 3, 4 or other numbers. The number of the second polarity fine grids 12 may be 1, 2, 3, 4 or other numbers. No limitation is made here. The number of the first polarity fine grids 11 and the number of the second polarity fine grids 12 may be the same or different.

[0063] Specifically, the first polarity fine grids 11 and the second polarity fine grids 12 are arranged along the first direction, and may be arranged alternately or non-alternatingly, and may be arranged at equal intervals or at unequal intervals along the first direction, which is not limited here.

[0064] Specifically, the first polarity fine grid 11 and the second polarity fine grid 12 are spaced apart, which means that a gap is formed between adjacent first polarity fine grids 11 and second polarity fine grids 12. The gap may be filled with an insulating member or may be an air gap.

[0065] The following descriptions of “the first polarity fine gate 11 includes the first gate line 111”, “the first polarity fine gate 11 includes the third gate line 113” and “the first polarity fine gate 11 includes the fifth gate line 114 and the sixth gate line 115” mean that the first gate line 111, the third gate line 113, the fifth gate line 114 and the sixth gate line 115 are all fine gates of the first polarity. The following descriptions of “the second polarity fine gate 12 includes the second gate line 121” and “the second polarity fine gate 12 includes the fourth gate line 122” mean that the second gate line 121 and the fourth gate line 122 are all fine gates of the second polarity.

[0066] See also Figure 1 , Figure 2 and Figure 3 In this embodiment, the first gate line 111 is a first polarity fine gate 11 closest to the edge of the silicon substrate 101. In this way, the risk of the electrical connector falling off from the end of the back contact battery 10 can be reduced.

[0067] It is understood that in other embodiments, the first gate line 111 may be located at a position away from the edge of the silicon substrate 101. For example, the first gate line 111 is the second, third, fourth or other numbered first polarity fine gate 11 from the edge. In this way, the risk of the electrical connector falling off from the middle position of the back contact battery 10 can be reduced. In this case, a bent second gate line 121 can be set on one side or both sides of the first gate line 111 to avoid the first connection block 112 provided on the first gate line 111.

[0068] Please refer to Figure 1 、 Figure 2 and Figure 3 , the first connection block 112 is disposed on the first gate line 111. That is, the first connection block 112 is connected to the first gate line 111.

[0069] Specifically, the first connection block 112 can penetrate the dielectric film layer 1003 to contact the first polar doping layer. The first connection block 112 and the first polar doping layer can also be isolated by the dielectric film layer 1003. The first connection block 112 can be made together with the first gate line 111. The first connection block 112 can also be made step by step with the first gate line 111.

[0070] In one example, the first connection block 112 and the first gate line 111 are made of the same paste, and both burn through the dielectric film layer 1003 to contact the first polar doping layer. In another example, the paste of the first gate line 111 burns through the dielectric film layer 1003 to contact the first polar doping layer, and the paste of the first connection block 112 does not burn through the dielectric film layer 1003.

[0071] In some embodiments, the first connection block 112 includes at least one of a pad and a gate line segment. In this way, the form of the first connection block 112 is diverse, which is beneficial to meeting more production scenarios and requirements. For example, the first connection block 112 includes a pad. Another example is that the first connection block 112 includes a gate line segment. Still another example is that the first connection block 112 includes a pad and a gate line segment. It can be understood that in the case where the first connection block 112 includes a gate line segment, the gate line segment penetrates the dielectric film layer 1003 to contact the first polar doping layer. In the case where the first connection block 112 includes a pad, the pad can penetrate the dielectric film layer 1003 to contact the first polar doping layer, or can also be isolated from the first polar doping layer by the dielectric film layer 1003.

[0072] Please note that in two adjacent back-contact cells 10, the electrical connector electrically connects the fine grids of one polarity in one back-contact cell 10 and electrically connects the fine grids of the other polarity in the other back-contact cell 10. The connection of the electrical connector in one back-contact cell 10 is discussed herein.

[0073] That is, in one back-contact cell 10, the first electrical connector is electrically connected to the first polar fine grid 11 and isolated from the second polar fine grid 12; the second electrical connector is electrically connected to the second polar fine grid 12 and isolated from the first polar fine grid 11. In other words, the fine grid polarities connected by one electrical connector in one back-contact cell 10 are the same. It can be understood that this does not mean that the electrical connector has a polarity and is the same as the polarity of the connected fine grid.

[0074] Specifically, the first electrical connector and the second electrical connector extend along the first direction and are alternately arranged along the second direction.

[0075] Specifically, the second-polarity fine grid 12 can be disconnected at the covering of the first electrical connector to avoid the first electrical connector; the second-polarity fine grid 12 can also be continuous at the covering of the first electrical connector and be electrically isolated from the first electrical connector by an insulating member. Similarly, the first-polarity fine grid 11 can be disconnected at the covering of the second electrical connector to avoid the second electrical connector; the first-polarity fine grid 11 can also be continuous at the covering of the second electrical connector and be electrically isolated from the second electrical connector by an insulating member.

[0076] Specifically, the first connection block 112 is used to connect the first electrical connector.

[0077] Further, the first connection block 112 and the first electrical connector can be electrically connected through at least one of conductive adhesive bonding, direct soldering, solder paste soldering, and physical contact. No limitation is made here.

[0078] Further, the entire area of the first connection block 112 is connected to the first electrical connector. In this way, the connection area is large, which is beneficial to improving the connection stability. It can be understood that in other embodiments, a partial area of the first connection block 112 can also be connected to the first electrical connector.

[0079] Further, the first electrical connector includes at least one of a solder ribbon and a conductive wire. In this text, the case where the first electrical connector is a solder ribbon is taken as an example for illustration. It can be understood that in the case where the first electrical connector is a solder ribbon, the embodiments of the present application can reduce the risk of the solder ribbon falling off the back-contact battery 10.

[0080] Specifically, the area of the back-contact battery 10 covered by the first electrical connector is the first pre-connection area.

[0081] Further, in the battery assembly, the number of first electrical connectors connected to the same back-contact battery 10 is multiple. In the back-contact battery 10, a first connection block 112 can be provided in each first pre-connection area, as Figure 3 shown. A first connection block 112 can also be provided in a partial first pre-connection area, and no first connection block 112 is provided in the remaining first pre-connection areas.

[0082] Even further, in the first pre-connection area, a first connection block 112 can be provided at each first-polarity fine grid 11. A first connection block 112 can also be provided at a partial first-polarity fine grid 11. No limitation is made here. In Figure 3 the example, first connection blocks 112 are provided at the first-polarity fine grids 11 at both ends of the first pre-connection area.

[0083] Please refer to Figure 1 and Figure 2, the width w1 of the first connection block 112 refers to the dimension of the first connection block 112 in the first direction. The width w1 of the first connection block 112 can be the same everywhere, can be different everywhere, or can be partially the same. The width w2 of the first gate line 111 refers to the dimension of the first gate line 111 in the first direction. The width w2 of the first gate line 111 can be the same everywhere, can be different everywhere, or can be partially the same.

[0084] Specifically, the width w1 of the first connection block 112 being greater than the width w2 of the first gate line 111 means that the width of at least one part of the first connection block 112 is greater than the width of at least one part of the first gate line 111. It can be that the minimum width of the first connection block 112 is greater than the maximum width of the first gate line 111; it can also be that the maximum width of the first connection block 112 is greater than the maximum width of the first gate line 111; it can also be that the maximum width of the first connection block 112 is greater than the width at the connection of the first gate line 111 and the first connection block 112. This is not limited here.

[0085] Please refer to Figure 2 , the length s1 of the first connection block 112 is greater than or equal to 100 μm. For example, it is 100 μm, 101 μm, 110 μm, 150 μm, 200 μm, 500 μm, 800 μm, 1000 μm, 1800 μm, 2000 μm, 5000 μm.

[0086] Specifically, the length s1 of the first connection block 112 refers to the dimension of the first connection block 112 in the second direction. The length s1 of the first connection block 112 can be the same everywhere, can be different everywhere, or can be partially the same.

[0087] The length s1 of the first connection block 112 being greater than or equal to 100 μm means that the length of at least one part of the first connection block 112 is greater than or equal to 100 μm. It can be that the minimum length of the first connection block 112 is greater than or equal to 100 μm, that is, the lengths of all parts of the first connection block 112 are greater than or equal to 100 μm; it can also be that the maximum length of the first connection block 112 is greater than or equal to 100 μm. This is not limited here.

[0088] Please refer to Figure 2 and Figure 4 , in some embodiments, the first connection block 112 is formed with a first hollow-out area 1120. In this way, while ensuring the coverage range of the first connection block 112, the material of the first connection block 112 can be reduced, which is beneficial to reducing costs while improving connection stability.

[0089] Please refer to Figure 5, in some embodiments, the first connection block 112 is solid. In this way, the area of the first connection block 112 can be increased as much as possible, thereby increasing the contact area between the first connection block 112 and the electrical connector, increasing the tensile force, reducing the risk of the electrical connector falling off the back-contact battery 10, and improving the connection stability between the back-contact battery 10 and the electrical connector.

[0090] Please refer to Figure 1 and Figure 2 , in some embodiments, the first connection block 112 is rectangular. It can be understood that in other embodiments, the first connection block 112 can be circular, annular, elliptical, triangular, racetrack-shaped or other shapes. The specific shape of the first connection block 112 is not limited herein.

[0091] Please refer to Figure 1 , Figure 2 and Figure 3 , the second gate line 121 includes a connected first main body portion 1211 and a first bending portion 1212. The first main body portion 1211 extends in a second direction, the second direction intersects the first direction, and the first bending portion 1212 is correspondingly arranged with the first connection block 112 and bends away from the first connection block 112 from the first main body portion 1211.

[0092] Specifically, the connection between the first main body portion 1211 and the first bending portion 1212 means that the first main body portion 1211 and the first bending portion 1212 are electrically connected and not disconnected.

[0093] Specifically, the first main body portion 1211 extending in the second direction means that the overall extension direction of the first main body portion 1211 is the second direction. This does not represent a limitation on the specific shape of the first main body portion 1211. In this embodiment, the first main body portion 1211 is linear, and the extension direction of the first main body portion 1211, that is, the second direction, is the length direction of the first main body portion 1211. In other embodiments, the first main body portion 1211 can also be wavy, zigzag or other shapes.

[0094] Specifically, the second direction intersecting the first direction means that the second direction does not overlap, is not the same as, and is not opposite to the first direction. In this embodiment, the first direction and the second direction are perpendicular to each other. The first direction and the second direction are respectively parallel to two adjacent long sides of the silicon substrate 101. It can be understood that in other embodiments, the first direction and the second direction can also form an acute angle or an obtuse angle; the first direction and the second direction can also form an acute angle or an obtuse angle with two adjacent long sides of the silicon substrate 101 respectively. No limitation is made herein. Please note that here "two adjacent long sides" refers to the sides of the silicon substrate 101 other than the corners, without considering the arc-shaped sides or short sides formed by rounding or chamfering the corners of the silicon substrate 101.

[0095] Specifically, the first bending portion 1212 is correspondingly arranged with the first connection block 112, which means that, regardless of the thickness of the first bending portion 1212 and the first connection block 112, in the first direction, the projections of the first bending portion 1212 and the first connection block 112 on the same plane at least partially overlap. In other words, the ranges occupied by the first bending portion 1212 and the first connection block 112 in the second direction at least partially overlap.

[0096] In this embodiment, the range occupied by the first bending portion 1212 in the second direction covers and exceeds the range occupied by the first connection block 112 in the second direction. In this way, by using the first bending portion 1212 to avoid the first connection block 112 as much as possible, more space can be provided for the first connection block 112 with a larger width as much as possible, which is convenient for widening the first connection block 112, and the short-circuit risk caused by too small an electrode spacing between two polarities can be reduced as much as possible.

[0097] It can be understood that in other embodiments, it can be that the range occupied by the first connection block 112 in the second direction covers and exceeds the range occupied by the first bending portion 1212 in the second direction; it can also be that the range occupied by the first connection block 112 in the second direction completely overlaps with the range occupied by the first bending portion 1212 in the second direction; it can also be that the range occupied by the first connection block 112 in the second direction intersects with the range occupied by the first bending portion 1212 in the second direction.

[0098] Specifically, the first bending portion 1212 bends away from the first connection block 112 from the first main body portion 1211, which means that in the first direction, the maximum distance between the first bending portion 1212 and the first main body portion 1211 is greater than 0.

[0099] Specifically, the first bending portion 1212 includes a first bending segment, a first connection segment and a second bending segment connected in sequence. The first bending segment connects one end of the first main body portion 1211 and the first connection segment, and the second bending segment connects the other end of the first main body portion 1211 and the first connection segment. In Figure 1 the example, the first connection segment is a straight line segment.

[0100] It can be understood that in other examples, the first bending portion 1212 can be in a wavy shape, a broken line shape or other forms. The first connection segment can be in a wavy shape, a broken line shape or other forms. No limitation is made here.

[0101] Please refer to Figure 1 and Figure 2In some embodiments, the difference between the width w1 of the first connection block 112 and the width w2 of the first gate line 111 is 5 μm-290 μm, for example, 5 μm, 8 μm, 10 μm, 50 μm, 80 μm, 100 μm, 150 μm, 200 μm, 280 μm, or 290 μm.

[0102] In this way, the width difference between the first connecting block 112 and the first gate line 111 is within an appropriate range, which can avoid the first connecting block 112 being too wide and the poor connection stability of the first electrical connector due to the difference being too small, and can also avoid the first connecting block 112 being too large and the current loss being too large due to the difference being too large.

[0103] See also Figure 1 and Figure 2 In some embodiments, the width w1 of the first connection block 112 is 10 μm-300 μm, for example, 10 μm, 12 μm, 20 μm, 50 μm, 100 μm, 150 μm, 200 μm, 250 μm, 280 μm, or 300 μm.

[0104] In this way, the width w1 of the first connecting block 112 is within an appropriate range, which can avoid the situation where the width is too small, resulting in a smaller contact width with the first electrical connector and poor connection stability of the first electrical connector, and can also avoid the situation where the series resistance of the first connecting block 112 is too large and the current loss is too large, resulting in a larger width.

[0105] See also Figure 1 and Figure 2 In some embodiments, the width w2 of the first gate line 111 is 5 μm-250 μm, for example, 5 μm, 7 μm, 10 μm, 50 μm, 100 μm, 150 μm, 200 μm, 240 μm, or 250 μm.

[0106] In this way, the width w2 of the first gate line 111 is within an appropriate range, which can avoid the gate line being easily disconnected and the poor effect of extracting carriers from the silicon substrate 101 due to a too small width, and can also avoid the excessive series resistance, large current loss and high cost due to a too large width.

[0107] See also Figure 1 and Figure 2 In some embodiments, the maximum distance d1 between the first bending portion 1212 and the first main body portion 1211 in the first direction is 5 μm-290 μm, for example, 5 μm, 8 μm, 10 μm, 50 μm, 80 μm, 100 μm, 150 μm, 200 μm, 280 μm, or 290 μm.

[0108] In this way, the maximum distance d1 between the first bending portion 1212 and the first main body portion 1211 in the first direction is within a suitable range, which can avoid the short - circuit risk caused by the small distance between the first bending portion 1212 with different polarities and the first connection block 112, and can also avoid the excessive total length of the second gate line 121, excessive series resistance, and large current loss caused by the large distance.

[0109] Please refer to Figure 1 and Figure 2 , in some embodiments, the first gate line 111, the first connection block 112, and the second gate line 121 satisfy the following formula:

[0110] -100μm ≤ w1 - w2 - d1 ≤ 100μm;

[0111] wherein, w1 is the width of the first connection block 112, w2 is the width of the first gate line 111, and d1 is the maximum distance between the first bending portion 1212 and the first main body portion 1211 in the first direction.

[0112] In this way, the difference between the width difference between the first connection block 112 and the first gate line 111 and the maximum bending depth of the first bending portion 1212 is within a suitable range, which can avoid the situation that the maximum bending depth of the first bending portion 1212 is too large compared with the width difference between the first connection block 112 and the first gate line 111 when the difference is too small, resulting in too large series resistance of the second gate line 121 while it is difficult to significantly improve the short - circuit risk, and can also avoid the situation that the maximum bending depth of the first bending portion 1212 is too small compared with the width difference between the first connection block 112 and the first gate line 111 when the difference is too large, resulting in a large short - circuit risk.

[0113] Specifically, the value of w1 - w2 - d1 is, for example, - 100μm, - 80μm, - 50μm, - 20μm, 0μm, 10μm, 20μm, 50μm, 80μm, 100μm.

[0114] Preferably, the value of w1 - w2 - d1 is 0. That is, w1 - w2 = d1. In this way, considering both the short - circuit risk and the series resistance, the overall effect is better.

[0115] Please refer to Figure 1 and Figure 2 , in some embodiments, the first gate line 111 is the first - polarity fine gate 11 closest to the edge of the silicon substrate 101, and the distance x1 between the first gate line 111 and the edge is 0.4mm - 1mm. For example, it is 0.4mm, 0.5mm, 0.6mm, 0.7mm, 0.8mm, 0.9mm, 1mm.

[0116] In this way, the distance x1 between the first grid line 111 and the edge is within a proper range, which can avoid inconvenient lamination caused by too small a distance and can also avoid poor effect of collecting carriers caused by too large a distance.

[0117] Preferably, the distance x1 between the first grid line 111 and the edge is 0.5 mm - 0.8 mm. For example, it is 0.5 mm, 0.52 mm, 0.55 mm, 0.58 mm, 0.6 mm, 0.62 mm, 0.65 mm, 0.68 mm, 0.7 mm, 0.72 mm, 0.75 mm, 0.78 mm, 0.8 mm. In this way, the distance x1 between the first grid line 111 and the edge is further optimized, making the overall effect better.

[0118] Please refer to Figure 1 and Figure 2 , in some embodiments, the distance x2 from the first connection block 112 to the edge is 0.4 mm - 50 mm. For example, it is 0.4 mm, 0.5 mm, 1 mm, 5 mm, 10 mm, 20 mm, 30 mm, 40 mm, 48 mm, 50 mm.

[0119] In this way, the distance x2 from the first connection block 112 to the edge is within a proper range, which can avoid inconvenient lamination caused by too small a distance and can also avoid poor connection stability between the end region of the back contact battery 10 and the first electrical connector caused by too large a distance.

[0120] Preferably, the distance x2 from the first connection block 112 to the edge is 0.8 mm - 5 mm. For example, it is 0.8 mm, 0.82 mm, 0.9 mm, 1 mm, 2 mm, 3 mm, 4 mm, 5 mm. In this way, the distance x2 from the first connection block 112 to the edge is further optimized, making the connection stability between the back contact battery 10 and the first electrical connector better.

[0121] Please refer to Figure 6 , in some embodiments, the first polar fine grid 11 includes a third grid line 113. The third grid line 113 includes a connected second main body portion 1131 and a second bending portion 1132. The second main body portion 1131 extends in the second direction, and the second bending portion 1132 is correspondingly arranged with the first connection block 112 and bends away from the first connection block 112.

[0122] In this way, the bent third grid line 113 can provide more space for the first connection block 112 with a larger width and the second grid line 121 bent to avoid the first connection block 112, facilitating the widening of the first connection block 112, facilitating the bending of the second grid line 121, and reducing the short - circuit risk caused by too small an electrode spacing between the two polarities.

[0123] Specifically, the connection between the second main body portion 1131 and the second bending portion 1132 means that the second main body portion 1131 and the second bending portion 1132 are electrically connected and not disconnected.

[0124] Specifically, the second main body portion 1131 extending along the second direction means that the overall extending direction of the second main body portion 1131 is the second direction. This does not represent a limitation on the specific form of the second main body portion 1131. In this embodiment, the second main body portion 1131 is linear, and the extending direction of the second main body portion 1131, that is, the second direction, is the length direction of the second main body portion 1131. In other embodiments, the second main body portion 1131 may also be wavy, zigzag, or other forms.

[0125] Specifically, the second bending portion 1132 is correspondingly arranged with the first connection block 112, which means that, regardless of the thickness of the second bending portion 1132 and the first connection block 112, in the first direction, at least part of the projections of the second bending portion 1132 and the first connection block 112 on the same plane overlap. In other words, the ranges occupied by the second bending portion 1132 and the first connection block 112 in the second direction at least partially overlap.

[0126] In this embodiment, the range occupied by the second bending portion 1132 in the second direction covers and exceeds the range occupied by the first connection block 112 in the second direction. In this way, by using the second bending portion 1132 to avoid the first connection block 112 as much as possible, more space can be provided for the first connection block 112 with a larger width as much as possible, which is convenient for widening the first connection block 112, and the short - circuit risk caused by too small an electrode spacing between two polarities can be reduced as much as possible.

[0127] It can be understood that in other embodiments, it can be that the range occupied by the first connection block 112 in the second direction covers and exceeds the range occupied by the second bending portion 1132 in the second direction; it can also be that the range occupied by the first connection block 112 in the second direction completely overlaps with the range occupied by the second bending portion 1132 in the second direction; it can also be that the range occupied by the first connection block 112 in the second direction intersects with the range occupied by the second bending portion 1132 in the second direction.

[0128] Specifically, the second bending portion 1132 bending away from the first connection block 112 from the second main body portion 1131 means that in the first direction, the maximum distance between the second bending portion 1132 and the second main body portion 1131 is greater than 0.

[0129] Specifically, the second bent portion 1132 includes a third bent segment, a second connecting segment, and a fourth bent segment that are connected in sequence. The third bent segment connects the second main body portion 1131 and one end of the second connecting segment, and the fourth bent segment connects the second main body portion 1131 and the other end of the second connecting segment. In Figure 6 's example, the second connecting segment is a straight line segment.

[0130] It can be understood that in other examples, the second bent portion 1132 can be wavy, zigzag, or other shapes. The second connecting segment can be wavy, zigzag, or other shapes. It is not limited here.

[0131] Please note that the second gate line 121 is a bent second-polarity fine gate 12, and the third gate line 113 is a bent first-polarity fine gate 11. The second gate line 121 can be adjacent to the first gate line 111 or not adjacent to the first gate line 111. The third gate line 113 can be adjacent to the second gate line 121 or not adjacent to the second gate line 121.

[0132] In Figures 1 - 5 's example, the number of second gate lines 121 is 1, which is adjacent to the first gate line 111, and there is no third gate line 113. That is, along the direction away from the edge, the first gate line 111 and the second gate line 121 are arranged in sequence.

[0133] In Figure 6 's example, the number of second gate lines 121 is 2, and the number of third gate lines 113 is 1. One second gate line 121 is adjacent to the first gate line 111, and the third gate line 113 is located between the two second gate lines 121. That is, along the direction away from the edge, the first gate line 111, the second gate line 121, the third gate line 113, and the second gate line 121 are arranged in sequence.

[0134] It can be understood that in other examples, it can also be that along the direction away from the edge, the first gate line 111, the second gate line 121, the third gate line 113, the second gate line 121, and the third gate line 113 are arranged in sequence.

[0135] Please refer to Figure 6 , in some embodiments, along the direction away from the first connection block 112, the bending depths of the first bent portion 1212 and the second bent portion 1132 gradually decrease.

[0136] In this way, along the direction away from the first connection block 112, the bending depths of the bent portions gradually decrease, which can not only use the bent portions to avoid the first connection block 112 or adjacent bent portions and reduce the risk of short circuit, but also achieve a smooth transition from bending to flatness.

[0137] Specifically, the bending depth of the first bending portion 1212 is the maximum distance between the first bending portion 1212 and the first main body portion 1211 of the second gate line 121 in the first direction, that is, Figure 6 d1 shown in Figure 6 . The bending depth of the second bending portion 1132 is the maximum distance between the second bending portion 1132 and the second main body portion 1131 of the third gate line 113 in the first direction, that is,

[0138] d2 shown in Figure 6 . In the example of

[0139] , along the direction away from the edge, the first gate line 111, the second gate line 121, the third gate line 113, and the second gate line 121 are arranged in sequence, and the bending depths of the corresponding bending portions gradually decrease. Figure 6 Please refer to

[0140] . In some embodiments, for adjacent second gate lines 121 and third gate lines 113, the first bending portion 1212 and the second bending portion 1132 satisfy the following formula:

[0141] 50μm ≤ d1 - d2 ≤ 150μm;

[0142] wherein, d2 is the maximum distance between the second bending portion 1132 and the second main body portion 1131 in the first direction, and d1 is the maximum distance between the first bending portion 1212 and the first main body portion 1211 in the first direction.

[0143] In this way, the difference in the bending depths of adjacent second gate lines 121 and third gate lines 113 is within a suitable range, which can avoid the need to use more bent gate lines to achieve the transition from bending to flatness, increased process complexity, and lower production efficiency caused by too small a difference, and can also avoid insufficient bending depth of one gate line, close distance to the bending portion with opposite polarity, and high short - circuit risk caused by too large a difference.

[0144] Specifically, the value of d1 - d2 is, for example, 50μm, 52μm, 80μm, 90μm, 100μm, 120μm, 140μm, 150μm. Figure 1 , Figure 2 and Figure 3 . Please refer to

[0145] . In some embodiments, the first gate line 111 and the first connection block 112 provided on the first gate line 111 form a first conductive structure 1001, and each row of the first conductive structures 1001 is continuous.

[0146] In this way, each row of the first conductive structures 1001 is not disconnected and has no break points, so that the power of the back - contact battery 10 is better. Figure 1 , Figure 2and Figure 3 , in some embodiments, the second gate lines 121 in each row are continuous.

[0147] In this way, the second gate lines 121 in each row are not disconnected and have no breakpoints, resulting in better power of the back-contact battery 10.

[0148] Please refer to Figure 7 and Figure 8 , in some embodiments, the second-polarity fine grid 12 includes a fourth gate line 122. The fourth gate line 122 is provided with a second connection block 123, and the width w3 of the second connection block 123 is greater than the width w4 of the fourth gate line 122.

[0149] In this way, the contact area between the second connection block 123 and the second electrical connector is increased, the pulling force is increased, the risk of the second electrical connector falling off from the back-contact battery 10 is reduced, and the connection stability between the back-contact battery 10 and the second electrical connector is improved.

[0150] Please refer to Figure 7 and Figure 8 , in some embodiments, the fourth gate line 122 and the second gate line 121 are the same second-polarity fine grid 12. In this way, integrating the first bending portion 1212 and the second connection block 123 into the same second-polarity fine grid 12 can make the connection stability at this place stronger. Moreover, the design and manufacturing can be concentrated, which is beneficial to improving the manufacturing efficiency.

[0151] Please note that when the fourth gate line 122 and the second gate line 121 are the same second-polarity fine grid 12, the fourth gate line 122 and the second gate line 121 can be regarded as partial structures of the second-polarity fine grid 12 respectively.

[0152] It can be understood that in other examples, the fourth gate line 122 and the second gate line 121 can also be different second-polarity fine grids 12. This is not limited herein.

[0153] Specifically, the second connection block 123 is used to connect the second electrical connector.

[0154] Furthermore, the second connection block 123 and the second electrical connector can be electrically connected by at least one of conductive adhesive bonding, direct welding, solder paste welding, and physical contact. This is not limited herein.

[0155] Furthermore, the entire area of the second connection block 123 is connected to the second electrical connector. In this way, the connection area is large, which is beneficial to improving the connection stability. It can be understood that in other embodiments, a partial area of the second connection block 123 can also be connected to the second electrical connector.

[0156] Further, the second electrical connector includes at least one of a solder strip and a conductive wire. In this text, the second electrical connector is taken as an example of a solder strip for illustration. It can be understood that in the case where the second electrical connector is a solder strip, the embodiment of the present application can reduce the risk of the solder strip falling off from the back contact battery 10.

[0157] Specifically, the area of the back contact battery 10 covered by the second electrical connector is the second pre-connection area.

[0158] Further, in the battery assembly, the number of second electrical connectors connected to the same back contact battery 10 is multiple. In the back contact battery 10, a second connection block 123 can be provided in each second pre-connection area. A second connection block 123 can also be provided in some of the second pre-connection areas, and no second connection block 123 is provided in the remaining second pre-connection areas. Further, in the second pre-connection area, a second connection block 123 can be provided at each second polar fine grid 12. A second connection block 123 can also be provided at some of the second polar fine grids 12. This is not limited herein. In this embodiment, second connection blocks 123 are provided at the second polar fine grids 12 at both ends of the second pre-connection area.

[0159] In some embodiments, the second connection block 123 includes at least one of a pad and a grid line segment. In this way, the form of the second connection block 123 is diverse, which is beneficial to meeting more production scenarios and requirements. For example, the second connection block 123 includes a pad. Another example is that the second connection block 123 includes a grid line segment. Still another example is that the second connection block 123 includes a pad and a grid line segment. It can be understood that in the case where the second connection block 123 includes a grid line segment, the grid line segment passes through the dielectric film layer 1003 to contact the second polar doping layer. In the case where the second connection block 123 includes a pad, the pad can pass through the dielectric film layer 1003 to contact the second polar doping layer, or can also be isolated from the second polar doping layer by the dielectric film layer 1003.

[0160] Please refer to Figure 7 and Figure 8 , the width w3 of the second connection block 123 refers to the dimension of the second connection block 123 in the first direction. The width w3 of the second connection block 123 can be the same everywhere, can be different everywhere, or can be partially the same. The width w4 of the fourth grid line 122 refers to the dimension of the fourth grid line 122 in the first direction. The width w4 of the fourth grid line 122 can be the same everywhere, can be different everywhere, or can be partially the same.

[0161] Specifically, the width w3 of the second connection block 123 is greater than the width w4 of the fourth gate line 122, which means that the width of at least one part of the second connection block 123 is greater than the width of at least one part of the fourth gate line 122. It can be that the minimum width of the second connection block 123 is greater than the maximum width of the fourth gate line 122; it can also be that the maximum width of the second connection block 123 is greater than the maximum width of the fourth gate line 122; it can also be that the maximum width of the second connection block 123 is greater than the width at the connection of the fourth gate line 122 and the second connection block 123. No limitation is made here.

[0162] Please refer to Figure 8 and Figure 9 , in some embodiments, the second connection block 123 is formed with a second hollow area 1230. In this way, while ensuring the coverage range of the second connection block 123, the material of the second connection block 123 can be reduced, which is beneficial to reducing costs while improving the connection stability.

[0163] Please refer to Figure 10 , in some embodiments, the second connection block 123 is solid. In this way, the area of the second connection block 123 can be increased as much as possible, so as to increase the contact area between the second connection block 123 and the electrical connection member, increase the pulling force, reduce the risk of the electrical connection member falling off from the back contact battery 10, and improve the connection stability between the back contact battery 10 and the electrical connection member.

[0164] Please refer to Figure 7 and Figure 8 , in some embodiments, the second connection block 123 is rectangular. It can be understood that in other embodiments, the second connection block 123 can be circular, annular, elliptical, triangular, racetrack-shaped or other shapes. No specific shape of the second connection block 123 is limited here.

[0165] Please refer to Figure 7 and Figure 8 , in some embodiments, the difference between the width w3 of the second connection block 123 and the width w4 of the fourth gate line 122 is 5 μm - 290 μm. For example, it is 5 μm, 8 μm, 10 μm, 50 μm, 80 μm, 100 μm, 150 μm, 200 μm, 280 μm, 290 μm.

[0166] In this way, the width difference between the second connection block 123 and the fourth gate line 122 is within a suitable range, which can avoid the insufficient width of the second connection block 123 and the poor connection stability of the second electrical connection member caused by too small a difference, and can also avoid too large a series resistance of the second connection block 123 and large current loss caused by too large a difference.

[0167] Please refer to Figure 7 and Figure 8In some embodiments, the width w3 of the second connection block 123 is 10 μm-300 μm, for example, 10 μm, 12 μm, 20 μm, 50 μm, 100 μm, 150 μm, 200 μm, 250 μm, 280 μm, or 300 μm.

[0168] In this way, the width w3 of the second connecting block 123 is within an appropriate range, which can avoid the situation where the width is too small, resulting in a smaller contact width with the second electrical connector and poor connection stability of the second electrical connector, and can also avoid the situation where the width is too large, resulting in too large a series resistance of the second connecting block 123 and a larger current loss.

[0169] See also Figure 7 and Figure 8 In some embodiments, the width w4 of the fourth gate line 122 is 5 μm-250 μm, for example, 5 μm, 7 μm, 10 μm, 50 μm, 100 μm, 150 μm, 200 μm, 240 μm, or 250 μm.

[0170] In this way, the width w4 of the fourth gate line 122 is within an appropriate range, which can avoid the gate line being easily disconnected and the poor effect of extracting carriers from the silicon substrate 101 due to a too small width, and can also avoid the excessive series resistance, large current loss and high cost due to a too large width.

[0171] See also Figure 7 and Figure 8 In some embodiments, the difference between the area of ​​the first connection block 112 and the area of ​​the second connection block 123 is -400 μm. 2 ~400μm 2 . For example, -400μm 2 、-400μm 2 、-400μm 2 、-400μm 2 、-400μm 2 , 400μm 2 .

[0172] In this way, the difference between the area of ​​the first connecting block 112 and the area of ​​the second connecting block 123 is within an appropriate range, which can avoid a large difference in the area of ​​the first connecting block 112 and the second connecting block 123 caused by the difference being too small or too large, so that the contact area between the first connecting block 112 and the first electrical connector and the contact area between the second connecting block 123 and the second electrical connector are roughly the same, so that the pulling force of the first electrical connector and the second electrical connector on the connecting blocks is roughly the same, which is beneficial to improving the connection stability between the electrical connector and the back contact battery 10.

[0173] See also Figure 7 and Figure 8, in some embodiments, the first-polarity fine grid 11 adjacent to the second connection block 123 is disconnected at the position corresponding to the second connection block 123 to avoid the second connection block 123. In the second direction, the distance d3 between the second connection block 123 and the break point of the first grid line 111 is 0.2 mm - 1 mm. For example, it is 0.2 mm, 0.3 mm, 0.4 mm, 0.5 mm, 0.6 mm, 0.7 mm, 0.8 mm, 0.9 mm, 1 mm.

[0174] In this way, by utilizing the space of the first-polarity fine grid 11 adjacent to the second connection block 123, the range of the second connection block 123 is made larger, which is beneficial to increasing the contact area between the second connection block 123 and the second electrical connector and improving the connection stability. At the same time, the distance d3 between the second connection block 123 and the break point of the first grid line 111 is within a suitable range, which can avoid the risk of short circuit due to the too-close distance between the opposite electrodes caused by too small a distance, and can also avoid the poor carrier collection effect in the spacer area and the poor efficiency of the battery caused by too large a distance.

[0175] Specifically, the first-polarity fine grid 11 adjacent to the second connection block 123 is disconnected at the position corresponding to the second connection block 123, which means that the connection line of the two break points of the first-polarity fine grid 11 passes through the second connection block 123. In order to avoid the second connection block 123 with opposite polarity, the first-polarity fine grid 11 is disconnected to form two break points.

[0176] Preferably, the distance d3 between the second connection block 123 and the break point of the first grid line 111 is 0.3 mm - 0.6 mm. For example, it is 0.3 mm, 0.32 mm, 0.4 mm, 0.45 mm, 0.5 mm, 0.58 mm, 0.6 mm. In this way, the distance d3 between the second connection block 123 and the break point of the first grid line 111 is further optimized, taking into account the area of the second connection block 123 and the carrier collection, and the overall effect is better.

[0177] Please refer to Figure 7 and Figure 8 , in some embodiments, the fourth grid line 122 is the second-polarity fine grid 12 closest to the edge of the silicon substrate 101, and the distance x3 between the fourth grid line 122 and the edge is greater than 0.7 mm - 1.3 mm.

[0178] In this way, the distance x3 between the fourth grid line 122 and the edge is within a suitable range, which can avoid the inconvenience of lamination caused by too small a distance, and can also avoid the poor effect of collecting carriers caused by too large a distance.

[0179] Preferably, the distance x3 between the fourth gate line 122 and the edge is 0.8 mm - 1.1 mm. For example, it is 0.8 mm, 0.82 mm, 0.85 mm, 0.88 mm, 0.9 mm, 0.95 mm, 1 mm, 1.02 mm, 1.05 mm, 1.08 mm, 1.1 mm. In this way, the distance x3 between the fourth gate line 122 and the edge is further optimized, making the overall effect better.

[0180] It can be understood that in other embodiments, the fourth gate line 122 may be located at a position away from the edge of the silicon substrate 101. For example, the fourth gate line 122 is the second, third, fourth, or other numbered second-polarity fine gate 12 counted from the edge. In this way, the risk of the electrical connector falling off from a relatively middle position of the back-contact battery 10 can be reduced. In this case, the bent first-polarity fine gate 11 may be provided on one side or both sides of the fourth gate line 122 to avoid the second connection block 123 provided on the fourth gate line 122.

[0181] Please refer to Figure 7 and Figure 8 , in some embodiments, the distance x4 from the second connection block 123 to the edge of the silicon substrate 101 is 0.7 mm - 50 mm. For example, it is 0.7 mm, 0.8 mm, 1 mm, 5 mm, 10 mm, 20 mm, 30 mm, 40 mm, 48 mm, 50 mm.

[0182] In this way, the distance x4 from the second connection block 123 to the edge is within a suitable range, which can avoid inconvenient lamination caused by too small a distance and can also avoid poor connection stability between the end region of the back-contact battery 10 and the second electrical connector caused by too large a distance.

[0183] Preferably, the distance x4 from the second connection block 123 to the edge is 1 mm - 5 mm. For example, it is 1 mm, 1.02 mm, 1.5 mm, 2 mm, 3 mm, 4 mm, 4.5 mm, 5 mm. In this way, the distance x4 from the second connection block 123 to the edge is further optimized, making the connection stability between the back-contact battery 10 and the second electrical connector better.

[0184] Please refer to Figure 7 and Figure 8 , in some embodiments, the fourth gate line 122 is the second-polarity fine gate 12 closest to the edge of the silicon substrate 101, and the second connection block 123 is located on the side of the fourth gate line 122 facing the edge.

[0185] In this way, the space at the edge can be fully utilized, making the range of the second connection block 123 larger and the range of the connection solder tape larger, which is beneficial to improving the connection stability between the back-contact battery 10 and the second electrical connector.

[0186] In some embodiments, the second connection block 123 protrudes from the fourth gate line 122 towards both sides of the fourth gate line 122.

[0187] In this way, the space between both sides of the second connection block 123 and the dissimilar gate lines can be fully utilized, so that the range of the second connection block 123 is larger and the range of the connecting solder tape is larger, which is beneficial to improving the connection stability between the back contact cell 10 and the second electrical connector.

[0188] Please refer to Figure 11 , in some embodiments, the fourth gate line 122 includes a connected third main body portion 1221 and a third bending portion 1222. The third main body portion 1221 extends along the second direction, and the third bending portion 1222 bends from the third main body portion 1221 towards the direction away from the edge of the silicon substrate 101. The second connection block 123 is disposed on the third bending portion 1222.

[0189] In this way, the second connection block 123 is disposed at the portion where the fourth gate line 122 bends towards the direction away from the edge of the silicon substrate 101, which can make the position of the second connection block 123 farther from the edge of the silicon substrate 101, farther from the end of the second electrical connector, and closer to the middle of the second electrical connector. It can prevent the end of the second electrical connector from being difficult to reach the second connection block 123 near the edge of the silicon substrate 101 due to reasons such as offset or cutting error, making the second connection block 123 easier to connect with the second electrical connector and having higher connection stability.

[0190] Specifically, the third bending portion 1222 includes a fifth bending segment, a third connection segment, and a sixth bending segment connected in sequence. The fifth bending segment connects one end of the third main body portion 1221 and the third connection segment, and the sixth bending segment connects the other end of the third main body portion 1221 and the fourth connection segment. In Figure 11 example, the third connection segment is a straight line segment.

[0191] It can be understood that in other examples, the third bending portion 1222 can be in a wave shape, a broken line shape, or other shapes. The second connection segment can be in a wave shape, a broken line shape, or other shapes. It is not limited here.

[0192] Please refer to Figure 11 , in some embodiments, the maximum distance d4 between the third bending portion 1222 and the third main body portion 1221 in the first direction is 5 μm - 290 μm. For example, it is 5 μm, 8 μm, 10 μm, 50 μm, 80 μm, 100 μm, 150 μm, 200 μm, 280 μm, 290 μm.

[0193] Thus, the maximum distance d4 between the third bending portion 1222 and the third main body portion 1221 in the first direction is within a suitable range, which can avoid the short - circuit risk caused by the small distance between the third bending portion 1222 and the adjacent opposite - polarity fine grid, and can also avoid the large total length of the fourth grid line 122, large series resistance, and large current loss caused by the large distance.

[0194] Please refer to Figure 7 , in some embodiments, the fourth grid line 122 and the second connection block 123 provided on the fourth grid line 122 form a second conductive structure 1002, and each row of the second conductive structures 1002 is continuous.

[0195] Thus, each row of the second conductive structures 1002 is not disconnected and has no break points, making the power of the back - contact battery 10 better.

[0196] Please refer to Figure 12 and Figure 2 , in some embodiments, the silicon substrate 101 includes a plurality of first - polarity doping regions 13 and a plurality of second - polarity doping regions 14 arranged along the first direction. The first - polarity doping regions 13 are provided with first - polarity fine grids 11, and the second - polarity doping regions 14 are provided with second - polarity fine grids 12;

[0197] The first - polarity doping region 13 includes a first doping region 131. The first doping region 131 includes a first region 1311 and a second region 1312. The first region 1311 is provided with a first grid line 111, and the second region 1312 corresponds to the first connection block 112; the second - polarity doping region 14 includes a second doping region 141. The second doping region 141 includes a third region 1411 and a fourth region 1412. The third region 1411 is provided with the first main body portion 1211 of the second grid line 121, and the fourth region 1412 is provided with the first bending portion 1212 of the second grid line 121.

[0198] Thus, the doping regions of the two polarities correspond to the fine grids of the two polarities, which is convenient for fabricating the fine grids of the corresponding polarities on the doping regions and for realizing the electrical connection between the doping regions and the fine grids of the corresponding polarities, and is beneficial to reducing the process difficulty, improving the manufacturing efficiency, and reducing the cost.

[0199] Specifically, "the first region 1311 is provided with a first grid line 111" means that the first grid line 111 is in electrical contact with the first region 1311.

[0200] Specifically, "the second region 1312 corresponds to the first connection block 112" means that in the thickness direction of the back - contact battery 10, the projection of the first connection block 112 and the second region 1312 on the same plane at least partially overlap. The first connection block 112 can be in electrical contact with the second region 1312 or can be electrically isolated from the second region 1312.

[0201] Specifically, "the first main body portion 1211 of the second gate line 121 is provided in the third region 1411" means that the first main body portion 1211 of the second gate line 121 is in electrical contact with the third region 1411.

[0202] Specifically, "the first bent portion 1212 of the second gate line 121 is provided in the fourth region 1412" means that the first bent portion 1212 of the second gate line 121 is in electrical contact with the fourth region 1412.

[0203] Specifically, the first polar doping region 13 and the second polar doping region 14 can be formed in all regions of the silicon substrate 101, such that the first polar fine gate 11 and the second polar fine gate 12 are distributed in all regions of the silicon substrate 101; the first polar doping region 13 and the second polar doping region 14 can be formed in partial regions of the silicon substrate 101, such that the first polar fine gate 11 and the second polar fine gate 12 are distributed in partial regions of the silicon substrate 101.

[0204] Specifically, the first polar doping region 13 and the second polar doping region 14 have different polarities. The first polar doping region 13 corresponds to the first polar doping layer. The second polar doping region 14 corresponds to the second polar doping layer.

[0205] Specifically, the number of the first polar doping regions 13 can be 1, 2, 3, 4 or other numbers. The number of the second polar doping regions 14 can be 1, 2, 3, 4 or other numbers. No limitation is made herein. The number of the first polar doping regions 13 and the number of the second polar doping regions 14 can be the same or different.

[0206] Specifically, the first polar doping region 13 and the second polar doping region 14 are arranged along the first direction, which can be an alternating arrangement or a non - alternating arrangement along the first direction; they can be arranged at equal intervals or at unequal intervals along the first direction. No limitation is made herein.

[0207] It can be understood that a gap can be formed between adjacent first polar doping region 13 and second polar doping region 14, they can be in contact with each other, or other film layer structures can be provided.

[0208] In some embodiments, a dielectric film layer 1003 is provided between at least a pair of adjacent first polar doping region 13 and second polar doping region 14, and the dielectric film layer 1003 electrically isolates the first polar doping region 13 and the second polar doping region 14.

[0209] In this way, the electrical isolation between the first doping layer and the second doping layer is realized by using the dielectric film layer 1003. At the same time, the refractive index difference and surface passivation effect of the dielectric film layer 1003 can be used to reduce optical loss and carrier recombination.

[0210] Specifically, the dielectric film layer 1003 can be disposed between a pair of adjacent first-polarity doped regions 13 and second-polarity doped regions 14; it can also be disposed between multiple pairs of adjacent first-polarity doped regions 13 and second-polarity doped regions 14. In this embodiment, the dielectric film layer 1003 is disposed between all adjacent first-polarity doped regions 13 and second-polarity doped regions 14.

[0211] Specifically, the dielectric film layer 1003 covers the first doped layer and the second doped layer. The first-polarity fine grid 11 passes through the dielectric film layer 1003 to contact the first doped layer, and the second-polarity fine grid 12 passes through the dielectric film layer 1003 to contact the second doped layer. To better show the first-polarity doped region 13 and the second-polarity doped region 14, the part where the dielectric film layer 1003 covers the first-polarity doped region 13 and the second-polarity doped region 14 is omitted in the figure.

[0212] Specifically, the dielectric film layer 1003 includes at least one of an aluminum oxide layer, a silicon nitride layer, a silicon oxynitride layer, a silicon carbide layer, an amorphous silicon layer, and a silicon oxide layer.

[0213] In some embodiments, a trench is formed between the first-polarity doped region 13 and the second-polarity doped region 14, and the dielectric film layer 1003 is at least partially disposed in the trench.

[0214] In this way, the trench can be used to electrically isolate the first-polarity doped region 13 and the second-polarity doped region 14 inside the silicon substrate 101, reducing the risk of conduction between the first-polarity doped region 13 and the second-polarity doped region 14.

[0215] Specifically, "the dielectric film layer 1003 is at least partially disposed in the trench" means that a part of the dielectric film layer 1003 is disposed in the trench and the remaining part is disposed outside the trench, or the entire dielectric film layer 1003 is disposed in the trench.

[0216] Specifically, the trench is continuously disposed between the first-polarity doped region 13 and the second-polarity doped region 14. Or rather, the first-polarity doped region 13 and the second-polarity doped region 14 are separated by the trench. In this way, it is ensured that the first-polarity doped region 13 and the second-polarity doped region 14 cannot conduct across the trench.

[0217] In some embodiments, a tunneling layer is disposed between at least a pair of adjacent first-polarity doped regions 13 and second-polarity doped regions 14, and both the first-polarity doped region 13 and the second-polarity doped region 14 are in contact with the tunneling layer.

[0218] In this way, the reverse bias can be reduced, and the heating power when the back contact battery 10 becomes a load after being blocked in the component can be reduced. Moreover, the tunneling layer can play a passivation role and reduce the recombination at the junction of the first-polarity doped region 13 and the second-polarity doped region 14.

[0219] Specifically, the tunneling layer includes at least one of a silicon oxide layer, an aluminum oxide layer, and a silicon carbide layer.

[0220] In some embodiments, at least one pair of adjacent first-polarity doped regions 13 and second-polarity doped regions 14 are in contact with each other.

[0221] Thus, the reverse bias can be reduced, and the heating power of the back-contact battery 10 when it becomes a load after being blocked in the component can be reduced.

[0222] Specifically, the adjacent first-polarity doped regions 13 and second-polarity doped regions 14 may be in contact with each other in all regions in the vicinity, or may be in contact with each other in some regions in the vicinity.

[0223] Please refer to Figure 13 and Figure 14 , in some embodiments, the second region 1312 protrudes from the first region 1311.

[0224] Thus, the second region 1312 corresponding to the first connection block 112 protrudes from the first region 1311 provided with the first gate line 111, which can provide sufficient space for the first connection block 112 with a larger width. Moreover, when the first connection block 112 is disposed in the second region 1312 and is in electrical contact with the second region 1312, the short-circuit risk caused by the smaller edge distance between the first connection block 112 with a larger width and the first region 1311 and being too close to the adjacent second-polarity doped region 14 can be reduced.

[0225] Please refer to Figure 13 , specifically, the width W2 of the second region 1312 is greater than the width W1 of the first region 1311. Thus, the second region 1312 with a larger width can better correspond to the first connection block 112 with a larger width.

[0226] Specifically, the width W2 of the second region 1312 is 12 μm - 2000 μm. For example, it is 12 μm, 15 μm, 20 μm, 50 μm, 100 μm, 500 μm, 800 μm, 1000 μm, 1500 μm, 1800 μm, 2000 μm. Thus, the width W2 of the second region 1312 is within a suitable range, which can avoid insufficient setting area of the first connection block 112 and a large short-circuit risk caused by a smaller width, and can also avoid poor collection effect of carriers of the other polarity caused by an excessive width.

[0227] Preferably, the width W2 of the second region 1312 is 500 μm - 1500 μm. For example, it is 500 μm, 510 μm, 600 μm, 800 μm, 1000 μm, 1200 μm, 1400 μm, 1500 μm. In this way, the width W2 of the second region 1312 is further optimized, taking into account the short - circuit risk and the carrier collection effect, and the overall effect is better.

[0228] Specifically, the width W1 of the first region 1311 is 6 μm - 800 μm. In this way, the width W1 of the first region 1311 is within a suitable range, which can avoid insufficient setting area of the first gate line 111, large short - circuit risk, and poor carrier collection effect corresponding to the first gate line 111 caused by a small width, and can also avoid poor carrier collection effect of the other polarity caused by a large width.

[0229] Preferably, the width W1 of the first region 1311 is 10 μm - 600 μm. For example, it is 10 μm, 12 μm, 20 μm, 80 μm, 100 μm, 200 μm, 500 μm, 600 μm. In this way, the width W1 of the first region 1311 is further optimized, taking into account the short - circuit risk and the carrier collection effects of both polarities, and the overall effect is better.

[0230] It can be understood that in other embodiments, the widths of the first region 1311 and the second region 1312 can be the same. For example, on the basis of the Figure 13 example, the upper side of the second region 1312 is recessed, and the recessed depth is equal to the protruding depth of the lower side. In other embodiments, the width W2 of the second region 1312 can be less than the width W1 of the first region 1311. For example, on the basis of the Figure 13 example, the upper side of the second region 1312 is recessed, and the recessed depth is greater than the protruding depth of the lower side. This is not limited herein.

[0231] Please refer to Figure 13 , in some embodiments, in the first direction, the maximum depth H1 by which the second region 1312 protrudes from the first region 1311 is 5 μm - 290 μm. For example, it is 5 μm, 8 μm, 10 μm, 50 μm, 80 μm, 100 μm, 150 μm, 200 μm, 280 μm, 290 μm.

[0232] In this way, the maximum depth H1 by which the second region 1312 protrudes from the first region 1311 is within a suitable range, which can avoid insufficient setting area of the first connection block 112 and large short - circuit risk caused by a too small depth, and can also avoid being unfavorable for collecting carriers of the other polarity caused by a too large depth.

[0233] Please refer to Figure 14, in some embodiments, the side of the fourth region 1412 facing the second region 1312 is recessed from the third region 1411. In this way, the recessed fourth region 1412 cooperates with the protruding second region 1312 to make full use of the space, so that the arrangement of the doping regions is more reasonable, which is conducive to better collecting carriers and improving the photoelectric conversion efficiency of the battery.

[0234] Please refer to Figure 15 and Figure 16 , in some embodiments, the side of the fourth region 1412 facing away from the second region 1312 protrudes from the third region 1411.

[0235] In this way, the fourth region 1412 corresponding to the first bending portion 1212 protrudes from the third region 1411 provided with the first main body portion 1211, which can provide sufficient space for the bent first bending portion 1212 and reduce the short - circuit risk caused by the small edge distance between the bent first bending portion 1212 and the fourth region 1412 and being too close to the adjacent hetero - doping region.

[0236] Please refer to Figure 16 , in some embodiments, the side of the fourth region 1412 facing the second region 1312 is recessed from the third region 1411, and the side of the fourth region 1412 facing away from the second region 1312 protrudes from the third region 1411.

[0237] In this way, it can cooperate with the protruding second region 1312 to make full use of the space, so that the arrangement of the doping regions is more reasonable, which is conducive to better collecting carriers, and can also provide sufficient space for the bent first bending portion 1212, reducing the short - circuit risk caused by the small edge distance between the bent first bending portion 1212 and the fourth region 1412 and being too close to the adjacent hetero - doping region.

[0238] Specifically, the recessed depth and the protruding depth of the fourth region 1412 are the same. In this way, the size of the fourth region 1412 in the second direction is the same as that of the third region 1411, which is conducive to better collecting carriers.

[0239] It can be understood that in other embodiments, the recessed depth of the fourth region 1412 can be greater than the protruding depth or less than the protruding depth. This is not limited here.

[0240] Please refer to Figure 15 and Figure 16 , in some embodiments, in the first direction, the maximum depth H2 of the side of the fourth region 1412 facing away from the second region 1312 protruding from the third region 1411 is 1 μm - 500 μm. For example, it is 1 μm, 2 μm, 10 μm, 50 μm, 80 μm, 100 μm, 150 μm, 200 μm, 300 μm, 400 μm, 500 μm.

[0241] In this way, the maximum depth H2 at which the fourth region 1412 protrudes from the third region 1411 is within a suitable range, which can avoid the risk of short circuit caused by a small protrusion depth resulting in a small edge spacing between the first bending portion 1212 and the fourth region 1412 and being too close to the adjacent differently doped regions, and can also avoid a poor effect of collecting carriers due to an excessive protrusion depth.

[0242] Preferably, the maximum depth H2 at which the side of the fourth region 1412 facing away from the second region 1312 protrudes from the third region 1411 is 5 μm - 190 μm. For example, it is 5 μm, 6 μm, 10 μm, 50 μm, 80 μm, 100 μm, 150 μm, 180 μm, 190 μm. In this way, the maximum depth at which the fourth region 1412 protrudes from the third region 1411 is further optimized, taking into account the short - circuit risk and the collection of carriers, and the overall effect is better.

[0243] Specifically, the third region 1411 and the fourth region 1412 have the same width. In this way, it is beneficial to better collect carriers.

[0244] It can be understood that in other embodiments, it can also be that the width W4 of the fourth region 1412 is less than the width W3 of the third region 1411, as Figure 14 shown; it can also be that the width W4 of the fourth region 1412 is greater than the width W3 of the third region 1411, as Figure 15 shown. It is not limited here.

[0245] Please refer to Figure 15 and Figure 16 . In some embodiments, the side of the second region 1312 facing the fourth region 1412 protrudes from the first region 1311. In the first direction, the difference between the maximum depth H1 at which the second region 1312 protrudes from the first region 1311 and the maximum depth H2 at which the fourth region 1412 protrudes from the third region 1411 is 50 μm - 200 μm. For example, it is 50 μm, 52 μm, 80 μm, 100 μm, 120 μm, 150 μm, 180 μm, 200 μm.

[0246] In this way, the difference between the maximum depth at which the second region 1312 protrudes and the maximum depth at which the fourth region 1412 protrudes is within a suitable range, which can avoid the situation where the maximum depth at which the fourth region 1412 protrudes is similar to the maximum depth at which the second region 1312 protrudes due to a too - small difference, and the need for the adjacent differently doped regions to be recessed for avoidance, resulting in a greater process complexity. It can also avoid a large difference leading to a small width of the fourth region 1412, a poor effect of collecting carriers, and a greater short - circuit risk.

[0247] Specifically, the maximum depth H2 by which the fourth region 1412 protrudes from the third region 1411 is the same as the maximum depth by which the fourth region 1412 depresses from the third region 1411. In this way, the difference between the maximum depth by which the second region 1312 protrudes and the maximum depth by which the fourth region 1412 depresses is within a suitable range, which can avoid the situation where the maximum depth by which the fourth region 1412 depresses is close to the maximum depth by which the second region 1312 protrudes, the width of the fourth region 1412 is small, and the effect of collecting carriers is poor due to too small a difference, and can also avoid the situation where the depression of the fourth region 1412 and the protrusion of the second region 1312 do not match well, the space utilization is poor, and the effect of collecting carriers is poor due to too large a difference.

[0248] Please refer to Figure 17 、 Figure 18 and Figure 6 , in some embodiments, the first-polarity fine grid 11 includes a third grid line 113. The third grid line 113 includes a connected second main body portion 1131 and a second bent portion 1132. The second main body portion 1131 extends in the second direction, and the second bent portion 1132 is correspondingly arranged with the first connection block 112 and bends away from the first connection block 112 from the second main body portion 1131.

[0249] The first-polarity doping region 13 includes a third doping region 132. The third doping region 132 includes a fifth region 1321 and a sixth region 1322. The second main body portion 1131 of the third grid line 113 is provided in the fifth region 1321, and the second bent portion 1132 of the third grid line 113 is provided in the sixth region 1322.

[0250] In this way, the third doping region 132 corresponds to the third grid line 113, which facilitates fabricating the third grid line 113 on the third doping region 132 and facilitating the electrical connection between the third doping region 132 and the third grid line 113, and is beneficial to reducing the process difficulty, improving the fabrication efficiency and reducing the cost.

[0251] Specifically, "the second main body portion 1131 of the third grid line 113 is provided in the fifth region 1321" means that the second main body portion 1131 of the third grid line 113 is in electrical contact with the fifth region 1321.

[0252] Specifically, "the second bent portion 1132 of the third grid line 113 is provided in the sixth region 1322" means that the second bent portion 1132 of the third grid line 113 is in electrical contact with the sixth region 1322.

[0253] Please refer to Figure 15 and Figure 16In some embodiments, the sixth region 1322 is recessed from the fifth region 1321 on the side facing the second region 1312. In this way, the recessed sixth region 1322 cooperates with the protruding fourth region 1412 to fully utilize the space, making the arrangement of the doping regions more reasonable, which is conducive to better collection of carriers and improving the photoelectric conversion efficiency of the battery.

[0254] See also Figure 17 and Figure 18 In some embodiments, the sixth region 1322 protrudes from the fifth region 1321 on a side facing away from the second region 1312 .

[0255] In this way, the sixth region 1322 corresponding to the second bending portion 1132 protrudes from the fifth region 1321 provided with the second main body portion 1131, which can provide sufficient space for the bent second bending portion 1132, thereby reducing the risk of short circuit caused by the small edge distance between the bent second bending portion 1132 and the sixth region 1322 and being too close to the adjacent heterogeneous doped region.

[0256] See also Figure 18 In some embodiments, the side of the sixth region 1322 facing the second region 1312 is recessed from the fifth region 1321 , and the side of the sixth region 1322 facing away from the second region 1312 is protruded from the fifth region 1321 .

[0257] In this way, it is possible to cooperate with the protruding fourth region 1412 to fully utilize the space, making the arrangement of the doping areas more reasonable and conducive to better collection of carriers, and to provide sufficient space for the bent second bent portion 1132, thereby reducing the risk of short circuit caused by the small edge spacing between the bent second bent portion 1132 and the sixth region 1322 and being too close to the adjacent oppositely doped region.

[0258] Specifically, the recessed depth and the protruding depth of the sixth region 1322 are the same, so that the size of the sixth region 1322 in the second direction is the same as that of the fifth region 1321, which is conducive to better collection of carriers.

[0259] It can be understood that in other embodiments, the recessed depth of the sixth region 1322 may be greater than the protruding depth, or may be less than the protruding depth, which is not limited here.

[0260] See also Figure 18 In some embodiments, the fourth region 1412 protrudes from the third region 1411 on a side away from the second region 1312 , and the protrusion depths of the fourth region 1412 and the sixth region 1322 gradually decrease in a direction away from the second region 1312 .

[0261] In this way, the depth of the protrusion gradually decreases in the direction away from the second area 1312, and a transition from protrusion to smoothness can be achieved.

[0262] Specifically, the protrusion depth of the fourth region 1412 is the maximum depth at which the side of the fourth region 1412 facing away from the second region 1312 protrudes from the third region 1411 in the first direction in the second doping region 141, that is, Figure 18 the H2 shown in Figure 18 . The protrusion depth of the sixth region 1322 is the maximum depth at which the side of the sixth region 1322 facing away from the second region 1312 protrudes from the fifth region 1321 in the first direction in the third doping region 132, that is,

[0263] In Figure 18 the example of

[0264] Please refer to Figure 18 , in some embodiments, for adjacent second doping region 141 and third doping region 132, the fourth region 1412 and the sixth region 1322 satisfy the following formula:

[0265] 50μm ≤ H2 - H3 ≤ 200μm;

[0266] wherein, H2 is the maximum depth at which the side of the fourth region 1412 facing away from the second region 1312 protrudes from the third region 1411 in the first direction, and H3 is the maximum depth at which the side of the sixth region 1322 facing away from the second region 1312 protrudes from the fifth region 1321 in the first direction.

[0267] In this way, the difference in the protrusion depths of the adjacent second doping region 141 and third doping region 132 is within a suitable range, which can avoid the need to use more protrusions of the doping regions to achieve the transition from bending to smoothness, increased process complexity, and low production efficiency caused by too small a difference, and can also avoid insufficient protrusion depth of one doping region, a relatively short distance from the corresponding bending portion to the edge of the doping region, and a high short - circuit risk caused by too large a difference.

[0268] Specifically, the value of H2 - H3 is, for example, 50μm, 52μm, 80μm, 90μm, 100μm, 120μm, 140μm, 150μm, 180μm, 200μm.

[0269] In some embodiments, each row of the first doping regions 131 is continuous. In this way, each row of the first doping regions 131 is not disconnected, which makes the power of the back - contact battery 10 better.

[0270] In some embodiments, the second doping regions 141 in each row are continuous. In this way, the second doping regions 141 in each row are not disconnected, so that the power of the back contact battery 10 is better.

[0271] In some embodiments, the doping region closest to the edge of the silicon substrate 101 is a P region. In this way, the space at the edge can be utilized to increase the area of the P region, so that the area of the P region is relatively large, which is convenient for collecting carriers.

[0272] It can be understood that in other embodiments, the doping region closest to the edge of the silicon substrate 101 can also be an N region.

[0273] Please refer to Figure 19 and Figure 8 In some embodiments, the second-polarity fine grid 12 includes a fourth grid line 122. The fourth grid line 122 is provided with a second connection block 123, and the width of the second connection block 123 is greater than the width of the fourth grid line 122.

[0274] The second-polarity doping region 14 includes a fourth doping region 142. The fourth doping region 142 includes a seventh region 1421 and an eighth region 1422. The fourth grid line 122 is provided in the seventh region 1421, and the eighth region 1422 corresponds to the second connection block 123.

[0275] In this way, the fourth doping region 142 corresponds to the fourth grid line 122, which is convenient for fabricating the fourth grid line 122 on the fourth doping region 142, facilitating reduction of the process difficulty, improvement of the fabrication efficiency, and cost reduction.

[0276] Specifically, "the fourth grid line 122 is provided in the seventh region 1421" means that the fourth grid line 122 is in electrical contact with the seventh region 1421.

[0277] Specifically, "the eighth region 1422 corresponds to the second connection block 123" means that in the thickness direction of the back contact battery 10, the projection of the second connection block 123 and the eighth region 1422 on the same plane at least partially overlap. The second connection block 123 can be in electrical contact with the eighth region 1422 or can be electrically isolated from the eighth region 1422.

[0278] Please refer to Figure 19 and Figure 8 In some embodiments, the fourth doping region 142 and the second doping region 141 are the same second-polarity doping region 14. In this way, integrating the fourth region 1412 and the eighth region 1422 into the same second-polarity doping region 14 can make the connection stability at this location stronger with the second electrical connector. Moreover, the design and fabrication can be concentrated, which is conducive to improving the fabrication efficiency.

[0279] Please note that when the fourth doping region 142 and the second doping region 141 are the same second polarity doping region 14 , the fourth doping region 142 and the second doping region 141 can be respectively regarded as partial structures of the second polarity doping region 14 .

[0280] It can be understood that in other examples, the fourth doping region 142 and the second doping region 141 may also be different second polarity fine gates 12. This is not limited here. Figure 19 In some embodiments, the eighth region 1422 is electrically connected to the second connection block 123 , and the eighth region 1422 protrudes from the seventh region 1421 .

[0281] In this way, the eighth region 1422 corresponding to the second connection block 123 protrudes from the seventh region 1421 provided with the fourth gate line 122, which can provide sufficient space for the second connection block 123 with a larger width. In addition, when the second connection block 123 is provided in the eighth region 1422 and is in electrical contact with the eighth region 1422, the risk of short circuit caused by the second connection block 123 with a larger width being too close to the edge of the eighth region 1422 and being too close to the adjacent oppositely doped region can be reduced.

[0282] Specifically, the side of the eighth region 1422 facing the edge of the back contact battery 10 may protrude from the seventh region 1421, or the side of the eighth region 1422 facing away from the edge of the back contact battery 10 may protrude from the seventh region 1421, or both sides of the eighth region 1422 may protrude from the seventh region 1421. This is not limited here.

[0283] It is understood that in other embodiments, the eighth region 1422 may also be aligned with the seventh region 1421. The eighth region 1422 may also be recessed from the seventh region 1421. This is not limited here.

[0284] See also Figure 19 In some embodiments, the maximum depth H4 of the eighth region 1422 protruding from the seventh region 1421 is 5 μm-290 μm, for example, 5 μm, 8 μm, 10 μm, 50 μm, 80 μm, 100 μm, 150 μm, 200 μm, 280 μm, or 290 μm.

[0285] In this way, the maximum depth H4 of the eighth region 1422 protruding from the seventh region 1421 is within an appropriate range, which can avoid insufficient setting area of ​​the second connecting block 123 and greater short circuit risk caused by too small a depth, and can also avoid being unfavorable for collecting carriers of the other polarity due to too large a depth.

[0286] In some embodiments, each row of the fourth doping regions 142 is continuous. In this way, each row of the fourth doping regions 142 is not disconnected, so that the power of the back contact battery 10 is better.

[0287] See also Figure 20 In some embodiments, the fourth gate line 122 includes a third main body portion 1221 and a third bending portion 1222 connected to each other, the third main body portion 1221 extends along the second direction, the third bending portion 1222 bends from the third main body portion 1221 in a direction away from the edge of the silicon substrate 101, and the second connecting block 123 is disposed on the third bending portion 1222;

[0288] The fourth doping region 142 includes a ninth region 1423 , and the ninth region 1423 is provided with a third bending portion 1222 .

[0289] In this way, the ninth region 1423 of the fourth doping region 142 corresponds to the third bending portion 1222 of the fourth gate line 122 , which facilitates manufacturing the fourth gate line 122 on the fourth doping region 142 , thereby reducing process difficulty, improving manufacturing efficiency and reducing costs.

[0290] See also Figure 20 In some embodiments, the side of the ninth region 1423 facing away from the eighth region 1422 protrudes from the seventh region 1421 .

[0291] In this way, the ninth region 1423 corresponding to the third bending portion 1222 protrudes from the seventh region 1421 on which the third main body portion 1221 is provided, which can provide sufficient space for the bent third bending portion 1222, thereby reducing the risk of short circuit caused by the small edge spacing between the bent third bending portion 1222 and the ninth region 1423 and being too close to the adjacent oppositely doped region.

[0292] See also Figure 21 and Figure 22 In some embodiments, the first polarity fine gate 11 is a positive gate line, and the first polarity fine gate 11 includes a fifth gate line 114 and a sixth gate line 115 , and a spacing L2 between the sixth gate line 115 and an adjacent second polarity fine gate 12 is greater than a spacing L1 between the fifth gate line 114 and an adjacent second polarity fine gate 12 .

[0293] In this way, since the spacing between the sixth gate line 115 and the adjacent heterosexual fine gate in the first direction is greater than the spacing between the fifth gate line 114 and the adjacent heterosexual fine gate, sufficient space can be reserved on the silicon substrate 101 for setting up an anti-hot spot structure, thereby reducing the risk of short circuit caused by contact between fine gates with different polarities and doped regions.

[0294] Specifically, the distance L2 between the sixth gate line 115 and the adjacent second-polarity fine gate 12 is greater than the distance L1 between the fifth gate line 114 and the adjacent second-polarity fine gate 12, which means that the distance between the sixth gate line 115 and the adjacent second-polarity fine gate 12 at at least one place is greater than the distance between the fifth gate line 114 and the adjacent second-polarity fine gate 12 at at least one place. It can be that the minimum value of the distance L2 between the sixth gate line 115 and the adjacent second-polarity fine gate 12 is greater than the maximum value of the distance L1 between the fifth gate line 114 and the adjacent second-polarity fine gate 12; or it can be that the maximum value of the distance L2 between the sixth gate line 115 and the adjacent second-polarity fine gate 12 is greater than the maximum value of the distance L1 between the fifth gate line 114 and the adjacent second-polarity fine gate 12. No limitation is made here.

[0295] Please refer to Figure 22 and Figure 23 , the first-polarity doping region 13 includes a fifth doping region 133, the second-polarity doping region 14 includes a sixth doping region 143, the fifth doping region 133 includes an overlapping portion 1331 and a non-overlapping portion 1332, the sixth doping region 143 includes a main body 1431 and a protruding portion 1432, the main body 1431 is spaced from the fifth doping region 133, the protruding portion 1432 protrudes from the main body 1431 and overlaps with the overlapping portion 1331; the sixth gate line 115 is disposed on the non-overlapping portion 1332.

[0296] In this way, the protruding portion 1432 of the sixth doping region 143 overlaps with the overlapping portion 1331 of the fifth doping region 133, so an anti-thermal spot structure can be formed, the reverse bias voltage can be reduced, and the heating power when the back-contact cell 10 becomes a load after being shaded in the component can be reduced, thereby reducing the thermal spot risk. At the same time, the fifth gate line 114 is disposed on the non-overlapping portion 1332, reducing the short-circuit risk caused by the contact between the fine gates and doping regions with different polarities.

[0297] Specifically, the fifth gate line 114 is disposed outside the non-overlapping portion 1332.

[0298] Specifically, the main body 1431 and the fifth doping region 133 can be spaced by a trench. The main body 1431 and the non-overlapping portion 1332 can be spaced by a dielectric film layer 1003. No limitation is made here.

[0299] Specifically, the shape of the protruding portion 1432 can be rectangular, circular, square, triangular or other shapes. No limitation is made here.

[0300] Specifically, the sixth gate line 115 is disposed on the non-overlapping portion 1332, which means that the sixth gate line 115 is in electrical contact with the non-overlapping portion 1332.

[0301] Please refer to Figure 24 and Figure 25, in some embodiments, the sixth gate line 115 is provided with a third connection block 116, and the width L3 of the third connection block 116 is greater than the width L4 of the sixth gate line 115.

[0302] In this way, the contact area between the third connection block 116 and the first electrical connector can be increased, the pulling force can be increased, the risk of the first electrical connector falling off from the back contact battery 10 can be reduced, and the connection stability between the back contact battery 10 and the first electrical connector can be improved.

[0303] Specifically, the sixth gate line 115 is provided with a third connection block 116. That is, the third connection block 116 is connected to the sixth gate line 115.

[0304] Specifically, the third connection block 116 can penetrate the dielectric film layer 1003 to contact the first polar doping layer. The third connection block 116 and the first polar doping layer can also be isolated by the dielectric film layer 1003. The third connection block 116 can be made together with the sixth gate line 115. The third connection block 116 can also be made step by step with the sixth gate line 115.

[0305] In one example, the third connection block 116 and the sixth gate line 115 are made of the same paste, and both burn through the dielectric film layer 1003 to contact the first polar doping layer. In another example, the paste of the sixth gate line 115 burns through the dielectric film layer 1003 to contact the first polar doping layer, and the paste of the third connection block 116 does not burn through the dielectric film layer 1003.

[0306] In some embodiments, the third connection block 116 includes at least one of a pad and a gate line segment. In this way, the form of the third connection block 116 is diverse, which is beneficial to meeting more production scenarios and requirements. For example, the third connection block 116 includes a pad. Another example is that the third connection block 116 includes a gate line segment. Still another example is that the third connection block 116 includes a pad and a gate line segment. It can be understood that in the case where the third connection block 116 includes a gate line segment, the gate line segment penetrates the dielectric film layer 1003 to contact the first polar doping layer. In the case where the third connection block 116 includes a pad, the pad can penetrate the dielectric film layer 1003 to contact the first polar doping layer, or can also be isolated from the first polar doping layer by the dielectric film layer 1003.

[0307] Specifically, specifically, the third connection block 116 is used to connect the first electrical connector.

[0308] Further, the third connection block 116 and the first electrical connector can be electrically conducted through at least one of conductive adhesive bonding, direct welding, solder paste welding, and physical contact. No limitation is made here.

[0309] Further, the entire area of the third connection block 116 can be connected to the first electrical connector. Or a partial area of the third connection block 116 can be connected to the first electrical connector.

[0310] Specifically, the width L3 of the third connection block 116 refers to the dimension of the third connection block 116 in the first direction. The width L3 of the third connection block 116 may be the same everywhere, may be different everywhere, or may be partially the same. The width L4 of the sixth gate line 115 refers to the dimension of the sixth gate line 115 in the first direction. The width L4 of the sixth gate line 115 may be the same everywhere, may be different everywhere, or may be partially the same.

[0311] Specifically, the width L3 of the third connection block 116 being greater than the width L4 of the sixth gate line 115 means that the width of at least one part of the third connection block 116 is greater than the width of at least one part of the sixth gate line 115. It may be that the minimum width of the third connection block 116 is greater than the maximum width of the sixth gate line 115; it may also be that the maximum width of the third connection block 116 is greater than the maximum width of the sixth gate line 115; it may also be that the maximum width of the third connection block 116 is greater than the width at the connection of the sixth gate line 115 and the third connection block 116. It is not limited here.

[0312] In some embodiments, the third connection block is formed with a third hollow area. In this way, while ensuring the coverage range of the third connection block, the material of the third connection block can be reduced, which is beneficial to reducing costs while improving the connection stability.

[0313] In some embodiments, the third connection block is solid. In this way, the area of the third connection block can be increased as much as possible, thereby increasing the contact area between the third connection block and the electrical connector, increasing the pulling force, reducing the risk of the electrical connector falling off from the back contact battery 10, and improving the connection stability between the back contact battery 10 and the electrical connector.

[0314] In some embodiments, the third connection block is rectangular. It can be understood that in other embodiments, the third connection block may be circular, annular, elliptical, triangular, racetrack-shaped or other shapes. The specific shape of the third connection block is not limited here.

[0315] Please refer to Figure 21 、 Figure 22 and Figure 24 , in some embodiments, the distance L2 between the sixth gate line 115 and the adjacent second-polarity fine grid 12 is the first distance, the distance L1 between the fifth gate line 114 and the adjacent second-polarity fine grid 12 is the second distance, and the difference between the first distance and the second distance is 0.05 mm - 0.1 mm. For example, it is 0.05 mm, 0.06 mm, 0.07 mm, 0.08 mm, 0.09 mm, 0.1 mm.

[0316] In this way, the difference between the first distance and the second distance is within a suitable range, which can avoid insufficient space for setting the anti-thermal-spot structure caused by too small a difference, and can also avoid poor carrier collection effect caused by too large a difference.

[0317] Specifically, the interval L2 between the sixth gate line 115 and the adjacent second polarity fine gate 12 may be equal everywhere, or unequal everywhere, or partially equal and partially unequal.

[0318] Specifically, the interval L1 between the fifth gate line 114 and the adjacent second polarity fine gate 12 may be equal everywhere, or unequal everywhere, or partially equal and partially unequal.

[0319] Specifically, the difference between the first spacing and the second spacing may be a fixed value within a range of 0.05 mm to 0.1 mm, or may fluctuate within a range of 0.05 mm to 0.1 mm.

[0320] See also Figure 21 , Figure 22 and Figure 24 In some embodiments, the spacing L2 between the sixth gate line 115 and the adjacent second polarity fine gate 12 is 0.2 mm-0.8 mm, for example, 0.2 mm, 0.3 mm, 0.4 mm, 0.5 mm, 0.6 mm, 0.7 mm, or 0.8 mm.

[0321] In this way, the spacing L2 between the sixth gate line 115 and the adjacent second polarity fine gate 12 is within an appropriate range, which can avoid insufficient space for setting the anti-hot spot structure due to too small a spacing, and can also avoid poor carrier collection effect due to too large a spacing.

[0322] Specifically, the interval L2 between the sixth gate line 115 and the adjacent second polarity fine gate 12 may be a fixed value within the range of 0.2 mm-0.8 mm, or may fluctuate within the range of 0.2 mm-0.8 mm.

[0323] See also Figure 21 , Figure 22 and Figure 24 In some embodiments, the interval L1 between the fifth gate line 114 and the adjacent second polarity fine gate 12 is a second interval of 0.1 mm-0.7 mm.

[0324] In this way, the interval L1 between the fifth gate line 114 and the adjacent second polarity fine gate 12 is within an appropriate range, which can avoid dense gate lines and high cost caused by too small intervals, and can also avoid poor carrier collection effect caused by too large intervals.

[0325] Specifically, the interval L1 between the fifth gate line 114 and the adjacent second polarity fine gate 12 may be a fixed value within a range of 0.1 mm to 0.7 mm, or may fluctuate within a range of 0.1 mm to 0.7 mm.

[0326] See also Figure 21, in some embodiments, the number of the sixth gate lines 115 is multiple, and the number of the fine gate lines between two adjacent sixth gate lines 115 is 8 - 35. For example, it is 8, 10, 12, 15, 19, 20, 22, 25, 28, 30, 32, 35.

[0327] In this way, the number of the fine gate lines between two adjacent sixth gate lines 115 is within a proper range, which can avoid the situation that the number of the sixth gate lines 115 is large as a whole and the manufacturing efficiency is low due to the small number of the fine gate lines between two adjacent sixth gate lines 115, and can also avoid the poor effect of reducing the hot spot risk due to the large number of the fine gate lines between two adjacent sixth gate lines 115.

[0328] Specifically, in the back contact battery 10, the number of the sixth gate lines 115 can be multiple, forming multiple pairs of adjacent sixth gate lines 115. The number of the fine gate lines between multiple pairs of adjacent sixth gate lines 115 can be the same, different, or partially the same and the rest different.

[0329] Please refer to Figure 21 , in some embodiments, the spacing L5 between two adjacent sixth gate lines 115 is 6 mm - 16.8 mm. For example, it is 6 mm, 7 mm, 8 mm, 10 mm, 12 mm, 14 mm, 15 mm, 16 mm, 16.8 mm.

[0330] In this way, the spacing L5 between two adjacent sixth gate lines 115 is within a proper range, which can avoid the situation that the number of the sixth gate lines 115 is large as a whole and the manufacturing efficiency is low due to the small spacing, and can also avoid the poor effect of reducing the hot spot risk as a whole due to the large spacing.

[0331] Specifically, in the back contact battery 10, the number of the sixth gate lines 115 can be multiple, forming multiple pairs of adjacent sixth gate lines 115. The spacing L5 between multiple pairs of adjacent sixth gate lines 115 can be the same, different, or partially the same and the rest different.

[0332] Please refer to Figure 23 and 25 , in some embodiments, in the first direction, the depth L6 that the convex portion 1432 protrudes from the body 1431 is 40 μm - 500 μm. For example, it is 40 μm, 42 μm, 44 μm, 50 μm, 80 μm, 100 μm, 120 μm, 150 μm, 200 μm, 250 μm, 300 μm, 350 μm, 400 μm, 450 μm, 480 μm, 500 μm.

[0333] In this way, the depth L6 of the protrusion 1432 protruding from the main body 1431 is within a suitable range, which can avoid the insufficient contact area with the fifth doped region 133 or even the difficulty in contacting the fifth doped region 133 caused by too small a protrusion depth, and the poor effect of reducing the hot spot risk. It can also avoid the relatively short distance from the sixth gate line 115 and the relatively large short-circuit risk caused by too large a protrusion depth.

[0334] Specifically, the depth L6 of the protrusion 1432 protruding from the main body 1431 can be a fixed value within 40μm - 500μm, or can fluctuate within 40μm - 500μm. It is not limited here.

[0335] Please refer to Figure 23 and 25 , the width L7 of the overlapping portion 1331 is 45μm - 500μm. For example, it is 45μm, 48μm, 50μm, 100μm, 150μm, 200μm, 250μm, 300μm, 350μm, 400μm, 450μm, 480μm, 500μm.

[0336] In this way, the width L7 of the overlapping portion 1331 is within a suitable range, which can avoid the poor effect of reducing the hot spot risk caused by too small a width, and can also avoid the relatively short distance from the sixth gate line 115 and the relatively large short-circuit risk caused by too large a width.

[0337] Specifically, the width L7 of the overlapping portion 1331 refers to the dimension of the overlapping portion 1331 in the first direction.

[0338] Specifically, the width L7 of the overlapping portion 1331 can be a fixed value within 45μm - 500μm, or can fluctuate within 45μm - 500μm. It is not limited here.

[0339] Please refer to Figure 23 and 25 , the length L8 of the overlapping portion 1331 is 10μm - 2000μm. For example, it is 10μm, 12μm, 50μm, 100μm, 300μm, 500μm, 800μm, 1000μm, 1200μm, 1500μm, 1800μm, 2000μm.

[0340] In this way, the length L8 of the overlapping portion 1331 is within a suitable range, which can avoid the poor effect of reducing the hot spot risk caused by too large or too small a length.

[0341] Specifically, the length L8 of the overlapping portion 1331 can be a fixed value within 10μm - 2000μm, or can fluctuate within 10μm - 2000μm. It is not limited here.

[0342] Please refer to Figure 23 and25 The width ratio of the overlapping portion 1331 to the fifth doped region 133 is less than or equal to 85%. For example, it is 85%, 83%, 80%, 75%, 70%, 60%, 50%, 40%, 30%, 20%, 10%, 8%, 5%, 1%, 0.1%.

[0343] In this way, the width ratio of the overlapping portion 1331 to the fifth doped region 133 is within a suitable range, which can avoid the poor effect of reducing the hot spot risk caused by too small a ratio, and can also avoid the relatively short distance between the sixth gate line 115 and the hetero-doped region and the relatively large short-circuit risk caused by too large a ratio.

[0344] Specifically, the width of the fifth doped region 133 refers to the dimension of the fifth doped region 133 in the first direction.

[0345] Please refer to Figure 23 and 25 The distance L9 between the protruding portion 1432 and the third connection block 116 is greater than or equal to 50 μm. For example, it is 50 μm, 52 μm, 60 μm, 100 μm, 200 μm, 300 μm, 400 μm, 480 μm, 500 μm.

[0346] In this way, the distance L9 between the protruding portion 1432 and the third connection block 116 is within a suitable range, which can avoid the relatively large short-circuit risk caused by too small a distance, and can also avoid the poor effect of reducing the hot spot risk caused by too large a distance.

[0347] Specifically, the distance L9 between the protruding portion 1432 and the third connection block 116 can be a fixed value within the range greater than or equal to 50 μm, or can fluctuate within the range greater than or equal to 50 μm. It is not limited here.

[0348] In some embodiments, the silicon substrate includes a silicon substrate and a plurality of passivated contact structures provided on the silicon substrate, and at least one of the first-polarity fine grids and the second-polarity fine grids is electrically connected to the passivated contact structures. In this way, recombination can be reduced, which is beneficial to improving the photoelectric conversion efficiency.

[0349] In this embodiment, the passivated contact structures include a first passivated contact structure and a second passivated contact structure, which are electrically connected to the first-polarity fine grid and the second-polarity fine grid respectively. In this way, recombination at the first-polarity fine grid can be reduced, and recombination at the second-polarity fine grid can also be reduced, making the effect of improving the photoelectric conversion efficiency better.

[0350] Specifically, the first passivated contact structure and the second passivated contact structure can be spaced apart from each other. For example, the first passivated contact structure and the second passivated contact structure are spaced apart by the silicon substrate; for another example, the first passivated contact structure and the second passivated contact structure are spaced apart by an insulating film layer; for still another example, a gap is formed between the first passivated contact structure and the second passivated contact structure.

[0351] Specifically, the number of the first passivation contact structures may be 1, 2, 3 or other numbers. All the first-polarity fine grids may be electrically connected to the first passivation contact structures, or some of the first-polarity fine grids may be electrically connected to the first passivation contact structures, and the remaining first-polarity fine grids are not electrically connected to the first passivation contact structures.

[0352] Similarly, the number of the second passivation contact structures may be 1, 2, 3 or other numbers. All the second-polarity fine grids may be electrically connected to the second passivation contact structures, or some of the second-polarity fine grids may be electrically connected to the second passivation contact structures, and the remaining second-polarity fine grids are not electrically connected to the second passivation contact structures.

[0353] It can be understood that in other embodiments, it may also be that the first-polarity fine grids are electrically connected to the passivation contact structures and the second-polarity fine grids are not electrically connected to the passivation contact structures; or it may be that the first-polarity fine grids are not electrically connected to the passivation contact structures and the second-polarity fine grids are electrically connected to the passivation contact structures. This is not limited herein.

[0354] In some embodiments, the passivation contact structure includes a first passivation contact structure. The first passivation contact structure includes a first interface passivation layer and a first-polarity doping layer that are sequentially stacked on the silicon substrate. The first-polarity doping layer is electrically connected to the first-polarity fine grids. In this way, the tunneling effect can be realized by using the first interface passivation layer to reduce recombination, and the field passivation effect can be realized by using the first-polarity doping layer to reduce recombination.

[0355] Specifically, the first interface passivation layer includes at least one of a silicon oxide layer, an aluminum oxide layer, a silicon carbide layer, a hydrogenated silicon carbide layer, an amorphous silicon layer, a polycrystalline silicon layer, a nanocrystalline silicon layer, a mixed crystalline silicon layer, a silicon carbon oxide layer, a silicon oxynitride layer, and a silicon carbon oxynitride layer.

[0356] Specifically, the first-polarity doping layer includes at least one of a doped polycrystalline silicon layer, a doped single-crystalline silicon layer, a doped amorphous silicon layer, a doped nanocrystalline silicon layer, a doped mixed crystalline silicon layer, a doped silicon carbide layer, a doped silicon dioxide layer, a doped silicon carbon oxide layer, a doped silicon oxynitride layer, and a doped silicon carbon oxynitride layer.

[0357] In some embodiments, the passivation contact structure includes a second passivation contact structure. The second passivation contact structure includes a second interface passivation layer and a second-polarity doping layer that are sequentially stacked on the silicon substrate. The second-polarity doping layer is electrically connected to the second-polarity fine grids.

[0358] In this way, the tunneling effect can be realized by using the second interface passivation layer to reduce recombination, and the field passivation effect can be realized by using the second-polarity doping layer to reduce recombination.

[0359] Specifically, the second interface passivation layer includes at least one of a silicon oxide layer, an aluminum oxide layer, a silicon carbide layer, a hydrogenated silicon carbide layer, an amorphous silicon layer, a polycrystalline silicon layer, a nanocrystalline silicon layer, a mixed crystalline silicon layer, a silicon carbon oxide layer, a silicon oxynitride layer, and a silicon carbon oxynitride layer.

[0360] Specifically, the second polar doping layer includes at least one of a doped polycrystalline silicon layer, a doped single-crystalline silicon layer, a doped amorphous silicon layer, a doped nanocrystalline silicon layer, a doped mixed crystalline silicon layer, a doped silicon carbide layer, a doped silicon dioxide layer, a doped silicon carbon oxide layer, a doped silicon oxynitride layer, and a doped silicon carbon oxynitride layer.

[0361] It can be understood that one of the first polar doping layer and the second polar doping layer is a P-type doping layer, and the other is an N-type doping layer.

[0362] In some embodiments, the passivated contact structure includes a first passivated contact structure. The first passivated contact structure includes a third polar doping layer, a first interface passivation layer, and a first polar doping layer that are sequentially stacked on a silicon substrate. The first polar doping layer is electrically connected to the first polar fine grid.

[0363] In this way, not only can the tunneling effect be realized by using the first interface passivation layer and the field passivation effect be realized by using the first polar doping layer to reduce recombination, but also the separation electric field of surface electrons and holes can be formed by using the third polar doping layer to improve the field passivation effect. Moreover, the Fermi level of the third polar doping layer is different from that of the silicon substrate, which can change the Fermi level, increase the solid concentration of impurities (transition metals), and achieve an additional gettering effect.

[0364] Specifically, the third polar doping layer includes at least one of a doped polycrystalline silicon layer, a doped single-crystalline silicon layer, a doped amorphous silicon layer, a doped nanocrystalline silicon layer, a doped mixed crystalline silicon layer, a doped silicon carbide layer, a doped silicon dioxide layer, a doped silicon carbon oxide layer, a doped silicon oxynitride layer, and a doped silicon carbon oxynitride layer.

[0365] It can be understood that the third polar doping layer can be stacked on the silicon substrate. For example, the third polar doping layer is deposited on the silicon substrate. The third polar doping layer can also be an inward diffusion layer formed by diffusing into the silicon substrate.

[0366] Please note that the materials of the first polar doping layer and the third polar doping layer can be the same or different. The explanations and descriptions of the first interface passivation layer and the first polar doping layer can refer to the previous text. To avoid redundancy, they will not be elaborated here.

[0367] In some embodiments, the passivated contact structure includes a second passivated contact structure. The second passivated contact structure includes a fourth polar doping layer, a second interface passivation layer, and a second polar doping layer that are sequentially stacked on a silicon substrate. The second polar doping layer is electrically connected to the second polar fine grid.

[0368] In this way, not only can the tunneling effect be achieved by using the second interface passivation layer and the field passivation effect be achieved by using the second polar doping layer to reduce recombination, but also the separation electric field of surface electrons and holes can be enhanced by using the fourth polar doping layer to improve the field passivation effect. Moreover, since the Fermi level of the fourth polar doping layer is different from that of the silicon substrate, the Fermi level can be changed, the solid concentration of impurities (transition metals) can be increased, and an additional gettering effect can be achieved.

[0369] It can be understood that the fourth polar doping layer can be stacked on the silicon substrate. For example, the fourth polar doping layer is deposited on the silicon substrate. The fourth polar doping layer can also be an inner diffusion layer formed by diffusing into the silicon substrate.

[0370] Specifically, the fourth polar doping layer includes at least one of a doped polysilicon layer, a doped single-crystalline silicon layer, a doped amorphous silicon layer, a doped nanocrystalline silicon layer, a doped mixed-crystalline silicon layer, a doped silicon carbide layer, a doped silicon dioxide layer, a doped silicon carbon oxide layer, a doped silicon oxynitride layer, and a doped silicon carbon oxynitride layer.

[0371] Please note that the materials of the second polar doping layer and the fourth polar doping layer can be the same or different. For the explanations and descriptions of the second interface passivation layer and the second polar doping layer, reference can be made to the foregoing text. To avoid redundancy, they will not be elaborated here.

[0372] It can be understood that one of the third polar doping layer and the fourth polar doping layer is a P-type doping layer, and the other is an N-type doping layer.

[0373] Please note that in the description of this specification, the specific features, structures, materials, or characteristics described can be combined in a suitable manner in any one or more embodiments or examples. For example, Figure 26 and Figure 27 incorporate the features of multiple foregoing embodiments or examples.

[0374] The battery module of the embodiment of the present application includes the back-contact battery 10 of any one of the above.

[0375] In the battery module of the embodiment of the present application, since in the back-contact battery 10, the width of the first connection block 112 is greater than the width of the first grid line 111 and the length is greater than or equal to 100 μm, the contact area between the first connection block 112 and the electrical connector can be increased, the pulling force can be increased, the risk of the electrical connector falling off from the back-contact battery 10 can be reduced, and the connection stability between the back-contact battery 10 and the electrical connector can be improved. At the same time, since the first bending portion 1212 in the second grid line 121 bends away from the first connection block 112 from the first main body portion 1211, more space can be provided for the first connection block 112 with a larger width, which is convenient for widening the first connection block 112, and the short-circuit risk caused by too small electrode spacing between the two polarities can be reduced.

[0376] In this embodiment, multiple back-contact batteries 10 in the battery assembly can be connected in series in sequence to form a battery string, thereby realizing the series connection and current collection output of the current. For example, the connection of the battery cells can be realized by setting solder tapes (bus bars, interconnection bars), conductive backplates, etc.

[0377] It can be understood that in such an embodiment, the battery assembly may further include a metal frame, a backplate, a photovoltaic glass, and a glue film. The glue film can be filled between the front and back of the back-contact battery 10, and between the photovoltaic glass, adjacent battery cells, etc. As a filler, it can be a transparent colloid with good light transmittance and aging resistance. For example, the glue film can adopt an EVA glue film or a POE glue film, and the specific selection can be made according to the actual situation and is not limited here.

[0378] The photovoltaic glass can cover the glue film on the front of the back-contact battery 10. The photovoltaic glass can be ultra-white glass, which has a high light transmittance, high transparency, and excellent physical, mechanical, and optical properties. For example, the light transmittance of the ultra-white glass can reach more than 92%, and it can protect the back-contact battery 10 without affecting the efficiency of the back-contact battery 10 as much as possible. At the same time, the glue film can bond the photovoltaic glass and the back-contact battery 10 together, and the presence of the glue film can seal and insulate the back-contact battery 10 and prevent water and moisture.

[0379] The backplate can be attached to the glue film on the back of the back-contact battery 10. The backplate can protect and support the back-contact battery 10, and has reliable insulation, water resistance, and aging resistance. The backplate can have multiple choices and is usually tempered glass, plexiglass, aluminum alloy TPT composite glue film, etc., and its specific setting can be made according to the specific situation and is not limited here. The whole composed of the backplate, the back-contact battery 10, the glue film, and the photovoltaic glass can be set on the metal frame. The metal frame, as the main external support structure of the entire battery assembly, can stably support and install the battery assembly. For example, the battery assembly can be installed at the required installation position through the metal frame.

[0380] The photovoltaic system of the embodiment of the present application includes the above-mentioned battery assembly.

[0381] In the photovoltaic system according to the embodiment of the present application, in the back contact battery 10, since the width of the first connection block 112 is greater than the width of the first grid line 111 and the length is greater than or equal to 100 μm, the contact area between the first connection block 112 and the electrical connector can be increased, the pulling force can be increased, the risk of the electrical connector falling off from the back contact battery 10 can be reduced, and the connection stability between the back contact battery 10 and the electrical connector can be improved. At the same time, since the first bending portion 1212 in the second grid line 121 bends away from the first connection block 112 from the first main body portion 1211, more space can be provided for the first connection block 112 with a larger width, which is convenient for widening the first connection block 112, and the short-circuit risk caused by too small electrode spacing between two polarities can be reduced.

[0382] In this embodiment, the photovoltaic system can be applied in a photovoltaic power station, such as a ground power station, a rooftop power station, a water surface power station, etc., and can also be applied to devices or apparatuses that use solar energy for power generation, such as a user solar power supply, a solar street lamp, a solar car, a solar building, etc. Of course, it can be understood that the application scenarios of the photovoltaic system are not limited thereto, that is to say, the photovoltaic system can be applied in all fields that require solar power generation. Taking the photovoltaic power generation system network as an example, the photovoltaic system may include a photovoltaic array, a busbar box, and an inverter. The photovoltaic array can be an array combination of multiple battery modules. For example, multiple battery modules can form multiple photovoltaic arrays. The photovoltaic array is connected to the busbar box, and the busbar box can collect the current generated by the photovoltaic array. After the collected current flows through the inverter and is converted into alternating current required by the commercial power grid, it is connected to the commercial power grid to achieve solar power supply.

[0383] In the description of this specification, the descriptions with reference to terms such as "some embodiments", "schematic embodiments", "examples", "specific examples", or "some examples" etc. mean that the specific features, structures, materials, or characteristics described in connection with the embodiments or examples are included in at least one embodiment or example of the present application. In this specification, the schematic expressions of the above terms do not necessarily refer to the same embodiments or examples. Moreover, the specific features, structures, materials, or characteristics described can be combined in a suitable manner in any one or more embodiments or examples.

[0384] In addition, the above are only the preferred embodiments of the present application, and are not used to limit the present application. Any modifications, equivalent replacements, and improvements made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A back-contact battery, characterized in that, Including: A silicon substrate, including a silicon substrate and a plurality of passivated contact structures disposed on the silicon substrate; A plurality of first-polarity fine grids and a plurality of second-polarity fine grids, disposed on the silicon substrate, arranged along a first direction, the first-polarity fine grids and the second-polarity fine grids being spaced apart; at least one of the first-polarity fine grids and the second-polarity fine grids is electrically connected to the passivated contact structure; The first-polarity fine grid includes a first grid line, the first grid line is provided with a first connection block, the width of the first connection block is greater than the width of the first grid line, and the length of the first connection block is greater than or equal to 100 μm; The second-polarity fine grid includes a second grid line, the second grid line includes a connected first main body portion and a first bent portion, the first main body portion extends along a second direction, the second direction intersects the first direction, the first bent portion is disposed corresponding to the first connection block, and bends away from the first connection block from the first main body portion.

2. The back contact battery according to claim 1, characterized in that, The passivated contact structure includes a first passivated contact structure, the first passivated contact structure includes a first interface passivation layer and a first-polarity doping layer sequentially stacked on the silicon substrate, and the first-polarity doping layer is electrically connected to the first-polarity fine grid.

3. The back-contact battery according to claim 1, characterized in that, The passivated contact structure includes a second passivated contact structure, the second passivated contact structure includes a second interface passivation layer and a second-polarity doping layer sequentially stacked on the silicon substrate, and the second-polarity doping layer is electrically connected to the second-polarity fine grid.

4. The back contact battery according to claim 1, characterized in that, The passivated contact structure includes a first passivated contact structure, the first passivated contact structure includes a third-polarity doping layer, a first interface passivation layer and a first-polarity doping layer sequentially stacked on the silicon substrate, and the first-polarity doping layer is electrically connected to the first-polarity fine grid.

5. The back-contact battery according to claim 1, characterized in that, The passivated contact structure includes a second passivated contact structure, the second passivated contact structure includes a fourth-polarity doping layer, a second interface passivation layer and a second-polarity doping layer sequentially stacked on the silicon substrate, and the second-polarity doping layer is electrically connected to the second-polarity fine grid.

6. The back-contact battery according to claim 1, characterized in that, The difference between the width of the first connection block and the width of the first grid line is 5 μm - 290 μm.

7. The back contact battery according to claim 1, characterized in that, The maximum distance between the first bent portion and the first main body portion in the first direction is 5 μm - 290 μm.

8. The back-contact battery according to claim 1, wherein The first grid line, the first connection block and the second grid line satisfy the following formula: -100 μm ≤ w1 - w2 - d1 ≤ 100 μm; Wherein, w1 is the width of the first connection block, w2 is the width of the first grid line, and d1 is the maximum distance between the first bent portion and the first main body portion in the first direction.

9. The back contact battery according to claim 1, characterized in that, The first grid line is the first-polarity fine grid closest to the edge of the silicon substrate, and the distance between the first grid line and the edge is 0.4 mm - 1 mm.

10. The back-contact battery according to claim 1, characterized in that, The distance from the first connection block to the edge of the silicon substrate is 0.4 mm - 50 mm.

11. The back-contact battery according to claim 1, characterized in that, The first-polarity fine grid includes a third grid line, the third grid line includes a connected second main body portion and a second bent portion, the second main body portion extends along the second direction, the second bent portion is correspondingly arranged with the first connection block, and bends away from the first connection block from the second main body portion.

12. The back contact battery according to claim 11, characterized in that, Along the direction away from the first connection block, the bending depths of the first bent portion and the second bent portion gradually decrease.

13. The back-contact battery according to claim 11, wherein, For adjacent second grid lines and third grid lines, the first bent portion and the second bent portion satisfy the following formula: 50μm ≤ d1 - d2 ≤ 150μm; wherein, d2 is the maximum distance between the second bent portion and the second main body portion in the first direction, and d1 is the maximum distance between the first bent portion and the first main body portion in the first direction.

14. The back-contact battery according to claim 1, wherein The first grid line and the first connection block provided on the first grid line form a first conductive structure, and each row of the first conductive structures is continuous; and / or, each row of the second grid lines is continuous.

15. The back contact battery according to claim 14, characterized in that, The first connection block includes at least one of a pad and a grid line segment.

16. The back contact battery according to claim 14, characterized in that, The first connection block is formed with a hollow area; or, the first connection block is solid.

17. The back contact battery according to claim 1, wherein The second-polarity fine grid includes a fourth grid line, the fourth grid line is provided with a second connection block, and the width of the second connection block is greater than the width of the fourth grid line.

18. The back-contact battery according to claim 17, wherein, The difference between the width of the second connection block and the width of the fourth grid line is 5μm - 290μm.

19. The back-contact battery according to claim 17, characterized in that, The difference between the area of the first connecting block and the area of the second connecting block is -400 μm 2 ~400 μm 2 .

20. The back-contact battery according to claim 17, characterized in that, The first-polarity fine grid adjacent to the second connection block is disconnected at a position corresponding to the second connection block to avoid the second connection block. In the second direction, the distance between the second connection block and the break point of the first grid line is 0.2mm - 1mm.

21. The back contact battery according to claim 17, characterized in that, The fourth grid line is the second-polarity fine grid closest to the edge of the silicon substrate, and the distance between the fourth grid line and the edge is greater than 0.7mm - 1.3mm.

22. The back-contact battery according to claim 17, characterized in that, The distance from the second connection block to the edge of the silicon substrate is 0.7mm - 50mm.

23. The back contact battery according to claim 17, characterized in that, The fourth grid line is the second-polarity fine grid closest to the edge of the silicon substrate, and the second connection block is located on the side of the fourth grid line facing the edge.

24. The back contact battery according to claim 17, characterized in that, The second connection block protrudes from the fourth grid line to both sides of the fourth grid line.

25. The back-contact battery according to claim 17, characterized in that, The fourth grid line includes a connected third main body portion and a third bent portion, the third main body portion extends along the second direction, the third bent portion bends away from the edge of the silicon substrate from the third main body portion, and the second connection block is provided on the third bent portion.

26. The back contact battery according to claim 25, characterized in that, The maximum distance between the third bent portion and the third main body portion in the first direction is 5μm - 290μm.

27. The back-contact battery according to claim 17, characterized in that, The fourth grid line and the second grid line are the same second-polarity fine grid.

28. The back contact battery according to claim 17, wherein The fourth grid line and the second connection block provided on the fourth grid line form a second conductive structure, and each row of the second conductive structures is continuous.

29. The back contact battery according to claim 17, characterized in that, The second connection block includes at least one of a pad and a grid line segment.

30. The back contact battery according to claim 17, wherein, The second connection block is formed with a hollow area; or, the second connection block is solid.

31. The back contact battery according to claim 1, characterized in that, The silicon substrate includes a plurality of first-polarity doped regions and a plurality of second-polarity doped regions arranged along the first direction. The first-polarity fine grids are provided in the first-polarity doped regions, and the second-polarity fine grids are provided in the second-polarity doped regions; The first-polarity doped region includes a first doped region. The first doped region includes a first region and a second region. The first grid line is provided in the first region, and the second region corresponds to the first connection block; The second-polarity doped region includes a second doped region. The second doped region includes a third region and a fourth region. The first main portion of the second grid line is provided in the third region, and the first bent portion of the second grid line is provided in the fourth region.

32. The back-contact battery according to claim 31, characterized in that, The second region protrudes from the first region.

33. The back-contact battery according to claim 32, characterized in that, In the first direction, the maximum depth at which the second region protrudes from the first region is 5 μm - 290 μm.

34. The back-contact battery according to claim 31, characterized in that, One side of the fourth region facing away from the second region protrudes from the third region.

35. The back contact battery according to claim 34, characterized in that, In the first direction, the maximum depth at which the fourth region protrudes from the third region is 1 μm - 500 μm.

36. The back-contact battery according to claim 34, wherein, One side of the second region facing the fourth region protrudes from the first region. In the first direction, the difference between the maximum depth at which the second region protrudes from the first region and the maximum depth at which the fourth region protrudes from the third region is 50 μm - 200 μm.

37. The back contact battery according to claim 31, characterized in that, The first-polarity fine grid includes a third grid line. The third grid line includes a connected second main portion and a second bent portion. The second main portion extends along the second direction, and the second bent portion is correspondingly arranged with the first connection block and bends away from the first connection block; The first-polarity doped region includes a third doped region. The third doped region includes a fifth region and a sixth region. The second main portion of the third grid line is provided in the fifth region, and the second bent portion of the third grid line is provided in the sixth region.

38. The back-contact battery according to claim 37, wherein One side of the sixth region facing away from the second region protrudes from the fifth region.

39. The back contact battery according to claim 38, characterized in that, One side of the fourth region facing away from the second region protrudes from the third region. Along the direction away from the second region, the protruding depths of the fourth region and the sixth region gradually decrease.

40. The back-contact battery according to claim 39, characterized in that, For adjacent second doped regions and third doped regions, the fourth region and the sixth region satisfy the following formula: 50 μm ≤ H2 - H3 ≤ 200 μm; wherein, H2 is the maximum depth at which one side of the fourth region facing away from the second region protrudes from the third region in the first direction, and H3 is the maximum depth at which one side of the sixth region facing away from the second region protrudes from the fifth region in the first direction.

41. The back contact battery according to claim 31, wherein, Each row of the first doped regions is continuous; and / or, each row of the second doped regions is continuous.

42. The back contact battery according to claim 31, wherein, The doped region closest to the edge of the silicon substrate is a P region.

43. The back contact battery according to claim 31, wherein, The second-polarity fine grid includes a fourth grid line. The fourth grid line is provided with a second connection block, and the width of the second connection block is greater than the width of the fourth grid line; The second polar doping region includes a fourth doping region, the fourth doping region includes a seventh region and an eighth region, the fourth gate line is provided in the seventh region, and the eighth region corresponds to the second connection block.

44. The back-contact battery according to claim 43, wherein, The eighth region protrudes from the seventh region.

45. The back contact battery according to claim 44, characterized in that, The maximum depth of the protrusion of the eighth region from the seventh region is 5 μm - 290 μm.

46. The back contact battery according to claim 43, characterized in that, The fourth doping region and the second doping region are the same second polar doping region.

47. The back contact battery according to claim 43, wherein, Each row of the fourth doping regions is continuous.

48. The back contact battery according to claim 43, wherein, The fourth gate line includes a connected third main body portion and a third bent portion. The third main body portion extends along the second direction, and the third bent portion bends from the third main body portion in a direction away from the edge of the silicon substrate. The second connection block is provided on the third bent portion; The fourth doping region includes a ninth region, and the third bent portion is provided in the ninth region.

49. The back-contact battery according to claim 48, characterized in that, One side of the ninth region facing away from the eighth region protrudes from the seventh region.

50. The back-contact battery according to claim 1, characterized in that, The first polar fine gate is a positive gate line. The first polar fine gate includes a fifth gate line and a sixth gate line. The distance between the sixth gate line and an adjacent second polar fine gate is greater than the distance between the fifth gate line and the adjacent second polar fine gate.

51. The back-contact battery according to claim 50, characterized in that, A third connection block is provided on the sixth gate line, and the width of the third connection block is greater than the width of the sixth gate line.

52. The back-contact battery according to claim 50, characterized in that, The distance between the sixth gate line and an adjacent second polar fine gate is a first distance, the distance between the fifth gate line and the adjacent second polar fine gate is a second distance, and the difference between the first distance and the second distance is 0.05 - 0.1 mm.

53. A battery assembly, characterized in that, Including the back contact battery according to any one of claims 1 - 52.

54. A photovoltaic system, characterized in that, Including the battery assembly according to claim 53.

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