Back contact cell, cell assembly and photovoltaic system

Abstract

The utility model discloses a back contact cell, a cell assembly and a photovoltaic system, an edge area of the back contact cell is provided with a third doping layer, and the third doping layer comprises a first doping segment, a fourth doping segment, a second doping segment and a third doping segment which are successively arranged along a clockwise direction. The first doped section is arranged at the first edge and continuously extends along the second direction, the second doped section is arranged at the second edge and continuously extends along the second direction, and the third doped section is arranged at the third edge and continuously extends along the first direction; the fourth doping section is arranged at the fourth edge and continuously extends in the first direction, any two doping types of the first doping section, the second doping section, the third doping section and the fourth doping section are P-type doping, and the other two doping types are N-type doping. The back contact provided by the utility model can reduce electric leakage caused by edge winding degree.

Description

Technical Field

[0001] This utility model relates to the field of solar cell technology, and more particularly to a back contact battery, battery module and photovoltaic system. Background Technology

[0002] Solar cell power generation is a sustainable and clean energy source that utilizes the photovoltaic effect of semiconductor PN junctions to convert sunlight into electrical energy. In solar cells, back-contact solar cells are those where both the P-region and N-region are located on the back (non-light-receiving surface) of the cell. The light-receiving surface of this cell has no metal electrodes obstructing it, thus effectively increasing the short-circuit current of the cell.

[0003] In related technologies, in back-contact batteries, both the doped layer and the electrodes are designed on the back side, requiring an intersecting P-region and N-region design. On the sides of the back-contact battery, the two doped layers may overlap due to edge plating, leading to leakage areas. Therefore, reducing leakage caused by edge plating is a problem that needs to be solved. Utility Model Content

[0004] The technical problem to be solved by this utility model is to provide a back contact battery that reduces leakage caused by edge wrapping.

[0005] The technical problem to be solved by this utility model is to provide a battery module and a photovoltaic system.

[0006] To solve the above problems, this utility model provides a back contact battery, comprising:

[0007] A silicon substrate having opposing first and second surfaces, the first surface having opposing first and second edges along a first direction, and opposing third and fourth edges along a second direction, the second direction intersecting the first direction; the first surface including an edge region and a middle region, the edge region surrounding the middle region;

[0008] A third doped layer is disposed on the edge region. The third doped layer includes a first doped segment, a fourth doped segment, a second doped segment, and a third doped segment arranged sequentially in a clockwise direction. The first doped segment is disposed at the first edge and extends continuously in the second direction. The second doped segment is disposed at the second edge and extends continuously in the second direction. The third doped segment is disposed at the third edge and extends continuously in the first direction. The fourth doped segment is disposed at the fourth edge and extends continuously in the first direction. Any two of the first, second, third, and fourth doped segments are P-type doped, and the other two are N-type doped.

[0009] In some embodiments, the first doping segment is P-type doped, the second doping segment is P-type doped, the third doping segment is N-type doped, and the fourth doping segment is N-type doped; or

[0010] The first doping segment is N-type doped, the second doping segment is N-type doped, the third doping segment is P-type doped, and the fourth doping segment is P-type doped; or

[0011] The first doping segment is P-type doped, the second doping segment is N-type doped, the third doping segment is N-type doped, and the fourth doping segment is P-type doped; or

[0012] The first doping segment is N-type doped, the second doping segment is P-type doped, the third doping segment is P-type doped, and the fourth doping segment is N-type doped; or

[0013] The first doping segment is P-type doped, the second doping segment is N-type doped, the third doping segment is P-type doped, and the fourth doping segment is N-type doped; or

[0014] The first doping segment is N-type doped, the second doping segment is P-type doped, the third doping segment is N-type doped, and the fourth doping segment is P-type doped.

[0015] In some embodiments, the back contact battery further includes a plurality of first doped layers, a plurality of second doped layers, a plurality of first connecting layers, and a plurality of second connecting layers disposed on the intermediate region. The plurality of first doped layers and the plurality of second doped layers are arranged alternately along the first direction and extend discontinuously along the second direction. The plurality of first connecting layers and the plurality of second connecting layers are arranged alternately along the second direction and extend along the first direction. The first doped layer is connected to the first connecting layer and disconnected at the second connecting layer. The second doped layer is connected to the second connecting layer and disconnected at the first connecting layer. The doping types of the first doped layer and the second doped layer are opposite.

[0016] In some embodiments, the first doping segment is P-type doped, the second doping segment is P-type doped, the third doping segment is N-type doped, the fourth doping segment is N-type doped, the first doped layer and the first connecting layer are P-type doped, and the second doped layer and the second connecting layer are N-type doped.

[0017] Furthermore, the first doped segment is connected to the end of the first connecting layer, and the second doped segment is connected to the end of the first connecting layer;

[0018] The third doped segment is connected to the end of the second doped layer, and the fourth doped segment is connected to the end of the second doped layer.

[0019] In some embodiments, the first doping segment is N-type doped, the second doping segment is N-type doped, the third doping segment is P-type doped, the fourth doping segment is P-type doped, the first doped layer and the first connecting layer are P-type doped, and the second doped layer and the second connecting layer are N-type doped.

[0020] Furthermore, the first doped segment is connected to the end of the second connecting layer, and the second doped segment is connected to the end of the second connecting layer;

[0021] The third doped segment is connected to the end of the first doped layer, and the fourth doped segment is connected to the end of the first doped layer.

[0022] In some embodiments, the first doping segment is P-type doped, the second doping segment is N-type doped, the third doping segment is N-type doped, the fourth doping segment is P-type doped, the first doped layer and the first connecting layer are P-type doped, and the second doped layer and the second connecting layer are N-type doped.

[0023] Furthermore, the first doped segment is connected to the fourth doped segment, and the second doped segment is connected to the third doped segment;

[0024] The first doped segment is connected to the end of the first connecting layer, and the second doped segment is connected to the end of the second connecting layer;

[0025] The third doped segment is connected to the end of the second doped layer, and the fourth doped segment is connected to the end of the first doped layer.

[0026] In some embodiments, the first doping segment is N-type doped, the second doping segment is P-type doped, the third doping segment is P-type doped, the fourth doping segment is N-type doped, the first doped layer and the first connecting layer are P-type doped, and the second doped layer and the second connecting layer are N-type doped.

[0027] Furthermore, the first doped segment is connected to the fourth doped segment, and the second doped segment is connected to the third doped segment;

[0028] The first doped segment is connected to the end of the second connecting layer, and the second doped segment is connected to the end of the first connecting layer;

[0029] The third doped segment is connected to the end of the first doped layer, and the fourth doped segment is connected to the end of the second doped layer.

[0030] In some embodiments, the first doping segment is P-type doped, the second doping segment is N-type doped, the third doping segment is P-type doped, the fourth doping segment is N-type doped, the first doped layer and the first connecting layer are P-type doped, and the second doped layer and the second connecting layer are N-type doped.

[0031] Furthermore, the first doped segment is connected to the third doped segment, and the second doped segment is connected to the fourth doped segment;

[0032] The first doped segment is connected to the end of the first connecting layer, and the second doped segment is connected to the end of the second connecting layer;

[0033] The third doped segment is connected to the end of the first doped layer, and the fourth doped segment is connected to the end of the second doped layer.

[0034] In some embodiments, the first doping segment is N-type doped, the second doping segment is P-type doped, the third doping segment is N-type doped, the fourth doping segment is P-type doped, the first doped layer and the first connecting layer are P-type doped, and the second doped layer and the second connecting layer are N-type doped.

[0035] Furthermore, the first doped segment is connected to the fourth doped segment, and the second doped segment is connected to the third doped segment;

[0036] The first doped segment is connected to the end of the second connecting layer, and the second doped segment is connected to the end of the first connecting layer;

[0037] The third doped segment is connected to the end of the first doped layer, and the fourth doped segment is connected to the end of the second doped layer.

[0038] To address the aforementioned problems, this utility model also provides a battery assembly comprising a plurality of the aforementioned back contact batteries.

[0039] To address the aforementioned problems, this utility model also provides a photovoltaic system, including the aforementioned battery module.

[0040] Implementing this utility model has the following beneficial effects:

[0041] This utility model discloses a back contact battery, which includes a third doped layer disposed on the edge region. The third doped layer includes a first doped segment, a fourth doped segment, a second doped segment, and a third doped segment arranged sequentially in a clockwise direction. The first doped segment is disposed at the first edge and extends continuously along the second direction, the second doped segment is disposed at the second edge and extends continuously along the second direction, the third doped segment is disposed at the third edge and extends continuously along the first direction, and the fourth doped segment is disposed at the fourth edge and extends continuously along the first direction. Any two of the first, second, third, and fourth doped segments are P-type doped, and the remaining two are N-type doped. The edge doped segments are double P-type doped and double N-type doped, and adjacent edge doped segments may be the same or different. This structure reduces the leakage region formed between the doped layer with edge winding and the back doped layer, and also reduces the leakage region formed by the interconnection between the doped layers plated around the four sides. Furthermore, this design is not limited to silicon wafer type and can be used for both N-type and P-type silicon wafers. Attached Figure Description

[0042] Figure 1 This is a schematic diagram of a photovoltaic system module provided in an embodiment of this application;

[0043] Figure 2 This is a schematic diagram of the planar structure of the silicon substrate of the back contact battery provided in the embodiments of this application;

[0044] Figure 3 This is a schematic diagram of the planar structure of the back contact battery provided in Embodiment 1 of this application;

[0045] Figure 4 This is a schematic diagram of the planar structure of the back contact battery provided in Embodiment 2 of this application;

[0046] Figure 5 This is a schematic diagram of the planar structure of the back contact battery provided in Embodiment 3 of this application;

[0047] Figure 6 This is a schematic diagram of the planar structure of the back contact battery provided in Embodiment 4 of this application;

[0048] Figure 7 This is a schematic diagram of the planar structure of the back contact battery provided in Embodiment 5 of this application;

[0049] Figure 8 This is a schematic diagram of the planar structure of the back contact battery provided in Embodiment 6 of this application.

[0050] Explanation of key component symbols:

[0051] Photovoltaic system 1000, battery module 200, back contact battery 100, silicon substrate 10, first surface 11, first edge 111, second edge 112, third edge 113, fourth edge 114, edge region 115, middle region 116, first doped layer 20, second doped layer 30, first connecting layer 40, second connecting layer 50, third doped layer 60, first doped segment 61, second doped segment 62, third doped segment 63, fourth doped segment 64. Detailed Implementation

[0052] To make the objectives, technical solutions, and advantages of this utility model clearer, the present utility model will be further described in detail below with reference to the accompanying drawings and embodiments. Examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain this utility model, and should not be construed as limiting this utility model. Furthermore, it should be understood that the specific embodiments described herein are merely for explaining this utility model and are not intended to limit this utility model.

[0053] In the description of this utility model, it should be understood that the terms "upper", "lower", "back surface", "front surface", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings. They are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model.

[0054] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on top" of the second feature includes the first feature directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature includes the first feature directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0055] In this utility model, "preferred" is only used to describe a better implementation method or embodiment, and should be understood as not constituting a limitation on the scope of protection of this utility model.

[0056] In this utility model, the technical features described in an open-ended manner include both closed technical solutions composed of the listed features and open technical solutions that include the listed features.

[0057] In this invention, numerical ranges are involved, and unless otherwise specified, the range includes the two endpoints of the numerical range.

[0058] Please see Figure 1 The photovoltaic system 1000 in this application embodiment may include the battery module 200 in this application embodiment. The battery module 200 in this application embodiment may include a plurality of back contact batteries 100 in this application embodiment. The plurality of back contact batteries 100 may be connected together in series by welding ribbon to form a plurality of battery strings. Each battery string may be connected in series, in parallel or in series-parallel manner to form the battery module 200.

[0059] like Figure 2 As shown, the silicon substrate 10 has opposing first surfaces 11 and second surfaces (not shown). The first surface 11 has opposing first edges 111 and second edges 112 along a first direction, and opposing third edges 113 and fourth edges 114 along a second direction, which intersects the first direction. The first surface 11 includes an edge region 115 and a central region 116, with the edge region 115 surrounding the central region 116.

[0060] Specifically, the first surface 11 can be the back side of the silicon substrate 10 (i.e., the backlight surface of the back contact cell 100), the second surface can be the front side of the silicon substrate 10, the first direction can be the longitudinal direction of the back contact cell 100, and the second direction can be the lateral direction of the back contact cell 100, with the two directions perpendicular to each other. Figure 2 In the example shown, the first edge 111 is the upper edge in the vertical direction, the second edge 112 is the lower edge in the vertical direction, the third edge 113 is the left edge in the horizontal direction, and the fourth edge 114 is the right edge in the horizontal direction. Exemplarily, the edge region 115 may be a region located at the four edges of the silicon substrate 10, which is generally U-shaped, and the edge region 115 is disposed around the middle region 116.

[0061] Please combine Figure 2 and Figure 3A plurality of first doped layers 20, a plurality of second doped layers 30, a plurality of first connecting layers 40, and a plurality of second connecting layers 50 are disposed on the intermediate region 116. The plurality of first doped layers 20 and the plurality of second doped layers 30 are arranged alternately along a first direction and extend discontinuously along a second direction. The plurality of first connecting layers 40 and the plurality of second connecting layers 50 are arranged alternately along the second direction and extend along the first direction. The first doped layer 20 is connected to the first connecting layer 40 and disconnected at the second connecting layer 50; the second doped layer 30 is connected to the second connecting layer 50 and disconnected at the first connecting layer 40. The doping types of the first doped layer 20 and the second doped layer 30 are opposite; the doping types of the first connecting layer 40 and the second connecting layer 50 are opposite; the doping types of the first connecting layer 40 and the first doped layer 20 are the same; and the doping types of the second connecting layer 50 and the second doped layer 30 are the same.

[0062] The third doped layer 60 is disposed on the edge region 115. The third doped layer 30 includes a first doped segment 61, a fourth doped segment 64, a second doped segment 62, and a third doped segment 63 arranged sequentially in a clockwise direction. The first doped segment 61 is disposed at the first edge 111 and extends continuously along the second direction. The second doped segment 62 is disposed at the second edge 112 and extends continuously along the second direction. The third doped segment 63 is disposed at the third edge 113 and extends continuously along the first direction. The fourth doped segment 64 is disposed at the fourth edge 114 and extends continuously along the first direction. Any two of the first doped segment 61, the second doped segment 62, the third doped segment 63, and the fourth doped segment 64 are P-type doped, and the other two are N-type doped.

[0063] It should be noted that, in the embodiments of this application, "discontinuous extension" can be understood as the structure being a segmented structure in its extension direction, with several interrupted regions in between. That is to say, in the text, "the first doped layer 20 and the second doped layer 30 extend discontinuously along the second direction" refers to the fact that from the third edge 113 to the fourth edge 114, the first doped layer 20 and the second doped layer 30 have several interrupted regions, and at the locations of these interrupted regions, a first connecting layer 40 and a second connecting layer 50 (e.g., ...) are disposed. Figure 3 As shown in the diagram, the first doped layer 20 breaks at the second interconnecting layer 50, and the second doped layer 30 breaks at the first interconnecting layer 40. In the following text, any description of "discontinuous extension" can be understood here.

[0064] Furthermore, "continuous extension" can be understood as a structure that is continuous and uninterrupted in the extension direction, without any breaks in the middle. That is to say, in this paper, the first doped segment 61, the second doped segment 62, and the third doped segments 63 and 64 are continuous and uninterrupted structures in their respective extension directions. In the following text, if there is a description of "continuous extension," please refer to this section for clarification.

[0065] The back contact battery disclosed in this utility model includes a third doped layer 30 disposed on the edge region 115. The third doped layer 30 includes a first doped segment 61, a fourth doped segment 64, a second doped segment 62, and a third doped segment 63 arranged sequentially in a clockwise direction. The first doped segment 61 is disposed at the first edge 111 and extends continuously along the second direction. The second doped segment 62 is disposed at the second edge 112 and extends continuously along the second direction. The third doped segment 63 is disposed at the third edge 113 and extends continuously along the first direction. The fourth doped segment 64 is disposed at the fourth edge 114 and extends continuously along the first direction. Any two of the first doped segment 61, the second doped segment 62, the third doped segment 63, and the fourth doped segment 64 are P-type doped, and the other two are N-type doped. The edge doped segments are double P-type doped and double N-type doped, and adjacent edge doped segments may be the same or different. This structure reduces leakage current caused by edge deflection and reduces the formation of leakage areas due to side surface deflection.

[0066] Specifically, in some embodiments, the first doped segment 61 may be located at the position of the first edge 111, where its upper edge coincides with the first edge 111, or there may be a preset distance between the upper edge of the first doped segment 61 and the first edge 111. This can be determined according to the specific manufacturing process and is not limited here. Similarly, the second doped segment 62 may be located at the position of the second edge 112, where its lower edge coincides with the second edge 112, or there may be a preset distance between the lower edge of the second doped segment 62 and the second edge 112. The third doped segment 63 may be located at the position of the third edge 113, where its left edge coincides with the third edge 113, or there may be a preset distance between the left edge of the third doped segment 63 and the third edge 113. The fourth doped segment 64 may be located at the position of the fourth edge 114, where its right edge coincides with the fourth edge 114, or there may be a preset distance between the right edge of the fourth doped segment 64 and the fourth edge 114. This is not limited here. The figure shows that each doped segment has a predetermined distance from the edge. This is merely illustrative to clearly show the presence of the silicon substrate 10, and it is not mandatory for each doped segment to have a predetermined distance from the edge. It is understood that having a predetermined distance between each doped segment and the edge can better isolate the side layer of the solar cell from the doped layer on the back of the solar cell, thereby further reducing leakage current caused by edge plating and achieving a better isolation effect.

[0067] For example, the first doped segment 61 may extend from the third edge 113 to the fourth edge 114; and / or, the second doped segment 62 may extend from the third edge 113 to the fourth edge 114; and / or, the third doped segment 63 may extend from the first edge 111 to the second edge 112; and / or, the fourth doped segment 63 may extend from the first edge 111 to the second edge 112.

[0068] Furthermore, in the intermediate region 116, the arrangement of each doped layer and the connecting layer is as follows: Figure 3 As shown, Figure 3 As shown, both the first doped layer 20 and the second doped layer 30 have several disconnected regions along the second direction. The disconnected regions of two adjacent first doped layers 20 are substantially aligned in the first direction, and the disconnected regions of two adjacent second doped layers 30 are also substantially aligned in the first direction. The first connecting layer 40 is disposed at the disconnected regions of the second doped layer 30, and is connected to the first doped layer 20 and insulated from the second doped layer 30. The second connecting layer 50 is disposed at the disconnected regions of the first doped layer 20, and is connected to the second doped layer 30 and insulated from the first doped layer 20.

[0069] In the embodiments of this application, the silicon substrate 10 can be either a P-type silicon substrate or an N-type silicon substrate, that is, the doping type of the silicon substrate 10 can be either P-type doping or N-type doping. The back contact battery provided in this application is not limited to the type of silicon wafer.

[0070] The present invention will be further illustrated below with specific embodiments.

[0071] Example 1

[0072] This embodiment provides a back contact battery, such as Figure 3 As shown, it includes:

[0073] A silicon substrate having opposing first and second surfaces, the first surface having opposing first and second edges along a first direction, and opposing third and fourth edges along a second direction, the second direction intersecting the first direction; the first surface including an edge region and a middle region, the edge region surrounding the middle region;

[0074] A plurality of first doped layers, a plurality of second doped layers, a plurality of first connecting layers, and a plurality of second connecting layers are disposed on the intermediate region. The plurality of first doped layers and the plurality of second doped layers are arranged alternately along a first direction and extend discontinuously along a second direction. The plurality of first connecting layers and the plurality of second connecting layers are arranged alternately along the second direction and extend along the first direction. The first doped layers are connected to the first connecting layers and disconnected at the second connecting layers. The second doped layers are connected to the second connecting layers and disconnected at the first connecting layers. The doping types of the first doped layers and the second doped layers are opposite.

[0075] A third doped layer is disposed on the edge region. The third doped layer includes a first doped segment, a fourth doped segment, a second doped segment, and a third doped segment arranged sequentially in a clockwise direction. The first doped segment is disposed at the first edge and extends continuously in the second direction. The second doped segment is disposed at the second edge and extends continuously in the second direction. The third doped segment is disposed at the third edge and extends continuously in the first direction. The fourth doped segment is disposed at the fourth edge and extends continuously in the first direction. Any two of the first, second, third, and fourth doped segments are P-type doped, and the other two are N-type doped.

[0076] Specifically, the first doping segment is P-type doped, the second doping segment is P-type doped, the third doping segment is N-type doped, the fourth doping segment is N-type doped, the first doped layer and the first connecting layer are P-type doped, and the second doped layer and the second connecting layer are N-type doped.

[0077] Furthermore, doped segments or doped layers with the same doping type are connected together, while doped segments or doped layers with different doping types are insulated from each other.

[0078] That is, the first doped segment is connected to the end of the first connecting layer, the second doped segment is connected to the end of the first connecting layer, the third doped segment is connected to the end of the second doped layer, and the fourth doped segment is connected to the end of the second doped layer.

[0079] Furthermore, the first doped segment is insulated from the second doped layer and the second connecting layer, and the first doped segment is insulated from the third doped segment and the fourth doped segment.

[0080] Furthermore, the second doped segment is insulated from the second doped layer and the second interconnecting layer, respectively; and the second doped segment is insulated from the third doped segment and the fourth doped segment, respectively.

[0081] Furthermore, the third doped segment is insulated from the first doped layer and the first connecting layer, and is also insulated from the first doped segment and the second doped segment.

[0082] Furthermore, the fourth doped segment is insulated from the first doped layer and the first connecting layer, and is also insulated from the first doped segment and the second doped segment.

[0083] It should be noted that in this embodiment, "insulation isolation" means that there is no electrical connection between the two. This can be achieved by directly forming a trench between the two, or by setting other insulating dielectric films between the two to achieve insulation between them. The specifics are not limited here, and the relevant descriptions below refer to this.

[0084] Example 2

[0085] This embodiment provides a back contact battery, such as Figure 4 As shown, it includes:

[0086] A silicon substrate having opposing first and second surfaces, the first surface having opposing first and second edges along a first direction, and opposing third and fourth edges along a second direction, the second direction intersecting the first direction; the first surface including an edge region and a middle region, the edge region surrounding the middle region;

[0087] A plurality of first doped layers, a plurality of second doped layers, a plurality of first connecting layers, and a plurality of second connecting layers are disposed on the intermediate region. The plurality of first doped layers and the plurality of second doped layers are arranged alternately along a first direction and extend discontinuously along a second direction. The plurality of first connecting layers and the plurality of second connecting layers are arranged alternately along the second direction and extend along the first direction. The first doped layers are connected to the first connecting layers and disconnected at the second connecting layers. The second doped layers are connected to the second connecting layers and disconnected at the first connecting layers. The doping types of the first doped layers and the second doped layers are opposite.

[0088] A third doped layer is disposed on the edge region. The third doped layer includes a first doped segment, a fourth doped segment, a second doped segment, and a third doped segment arranged sequentially in a clockwise direction. The first doped segment is disposed at the first edge and extends continuously in the second direction. The second doped segment is disposed at the second edge and extends continuously in the second direction. The third doped segment is disposed at the third edge and extends continuously in the first direction. The fourth doped segment is disposed at the fourth edge and extends continuously in the first direction. Any two of the first, second, third, and fourth doped segments are P-type doped, and the other two are N-type doped.

[0089] Specifically, the first doping segment is N-type doped, the second doping segment is N-type doped, the third doping segment is P-type doped, the fourth doping segment is P-type doped, the first doped layer and the first connecting layer are P-type doped, and the second doped layer and the second connecting layer are N-type doped.

[0090] Furthermore, doped segments or doped layers with the same doping type are connected together, while doped segments or doped layers with different doping types are insulated from each other.

[0091] That is, the first doped segment is connected to the end of the second connecting layer, the second doped segment is connected to the end of the second connecting layer; the third doped segment is connected to the end of the first doped layer, and the fourth doped segment is connected to the end of the first doped layer.

[0092] Furthermore, the first doped segment is insulated from the first doped layer and the first connecting layer, respectively, and the first doped segment is insulated from the third doped segment and the fourth doped segment, respectively.

[0093] Furthermore, the second doped segment is insulated from the first doped layer and the first connecting layer, respectively; and the second doped segment is insulated from the third doped segment and the fourth doped segment, respectively.

[0094] Furthermore, the third doped segment is insulated from the second doped layer and the second interconnecting layer, and is also insulated from the first doped segment and the second doped segment.

[0095] Furthermore, the fourth doped segment is insulated from the second doped layer and the second interconnecting layer, and is also insulated from the first doped segment and the second doped segment.

[0096] Example 3

[0097] This embodiment provides a back-contact battery string, such as Figure 5 As shown, it includes:

[0098] A silicon substrate having opposing first and second surfaces, the first surface having opposing first and second edges along a first direction, and opposing third and fourth edges along a second direction, the second direction intersecting the first direction; the first surface including an edge region and a middle region, the edge region surrounding the middle region;

[0099] A plurality of first doped layers, a plurality of second doped layers, a plurality of first connecting layers, and a plurality of second connecting layers are disposed on the intermediate region. The plurality of first doped layers and the plurality of second doped layers are arranged alternately along a first direction and extend discontinuously along a second direction. The plurality of first connecting layers and the plurality of second connecting layers are arranged alternately along the second direction and extend along the first direction. The first doped layers are connected to the first connecting layers and disconnected at the second connecting layers. The second doped layers are connected to the second connecting layers and disconnected at the first connecting layers. The doping types of the first doped layers and the second doped layers are opposite.

[0100] A third doped layer is disposed on the edge region. The third doped layer includes a first doped segment, a fourth doped segment, a second doped segment, and a third doped segment arranged sequentially in a clockwise direction. The first doped segment is disposed at the first edge and extends continuously in the second direction. The second doped segment is disposed at the second edge and extends continuously in the second direction. The third doped segment is disposed at the third edge and extends continuously in the first direction. The fourth doped segment is disposed at the fourth edge and extends continuously in the first direction. Any two of the first, second, third, and fourth doped segments are P-type doped, and the other two are N-type doped.

[0101] Specifically, the first doping segment is P-type doped, the second doping segment is N-type doped, the third doping segment is N-type doped, the fourth doping segment is P-type doped, the first doped layer and the first connecting layer are P-type doped, and the second doped layer and the second connecting layer are N-type doped.

[0102] Furthermore, doped segments or doped layers with the same doping type are connected together, while doped segments or doped layers with different doping types are insulated from each other.

[0103] That is, the first doped segment is connected to the fourth doped segment, and the second doped segment is connected to the third doped segment; the first doped segment is connected to the end of the first connecting layer, and the second doped segment is connected to the end of the second connecting layer; the third doped segment is connected to the end of the second doped layer, and the fourth doped segment is connected to the end of the first doped layer.

[0104] Furthermore, the first doped segment is insulated from the second doped layer and the second connecting layer, respectively, and the first doped segment is insulated from the third doped segment and the second doped segment, respectively.

[0105] Furthermore, the second doped segment is insulated from the first doped layer and the first connecting layer, respectively; and the second doped segment is insulated from the first doped segment and the fourth doped segment, respectively.

[0106] Furthermore, the third doped segment is insulated from the first doped layer and the first connecting layer, and the third doped segment is insulated from the first doped segment and the fourth doped segment.

[0107] Furthermore, the fourth doped segment is insulated from the second doped layer and the second interconnecting layer, and is also insulated from the third doped segment and the second doped segment.

[0108] Example 4

[0109] This embodiment provides a battery assembly, such as Figure 6 As shown, it includes:

[0110] A silicon substrate having opposing first and second surfaces, the first surface having opposing first and second edges along a first direction, and opposing third and fourth edges along a second direction, the second direction intersecting the first direction; the first surface including an edge region and a middle region, the edge region surrounding the middle region;

[0111] A plurality of first doped layers, a plurality of second doped layers, a plurality of first connecting layers, and a plurality of second connecting layers are disposed on the intermediate region. The plurality of first doped layers and the plurality of second doped layers are arranged alternately along a first direction and extend discontinuously along a second direction. The plurality of first connecting layers and the plurality of second connecting layers are arranged alternately along the second direction and extend along the first direction. The first doped layers are connected to the first connecting layers and disconnected at the second connecting layers. The second doped layers are connected to the second connecting layers and disconnected at the first connecting layers. The doping types of the first doped layers and the second doped layers are opposite.

[0112] A third doped layer is disposed on the edge region. The third doped layer includes a first doped segment, a fourth doped segment, a second doped segment, and a third doped segment arranged sequentially in a clockwise direction. The first doped segment is disposed at the first edge and extends continuously in the second direction. The second doped segment is disposed at the second edge and extends continuously in the second direction. The third doped segment is disposed at the third edge and extends continuously in the first direction. The fourth doped segment is disposed at the fourth edge and extends continuously in the first direction. Any two of the first, second, third, and fourth doped segments are P-type doped, and the other two are N-type doped.

[0113] Specifically, the first doping segment is N-type doped, the second doping segment is P-type doped, the third doping segment is P-type doped, the fourth doping segment is N-type doped, the first doped layer and the first connecting layer are P-type doped, and the second doped layer and the second connecting layer are N-type doped.

[0114] Furthermore, doped segments or doped layers with the same doping type are connected together, while doped segments or doped layers with different doping types are insulated from each other.

[0115] That is, the first doped segment is connected to the fourth doped segment, and the second doped segment is connected to the third doped segment; the first doped segment is connected to the end of the second connecting layer, and the second doped segment is connected to the end of the first connecting layer; the third doped segment is connected to the end of the first doped layer, and the fourth doped segment is connected to the end of the second doped layer.

[0116] Furthermore, the first doped segment is insulated from the first doped layer and the first connecting layer, and the first doped segment is insulated from the third doped segment and the second doped segment, respectively.

[0117] Furthermore, the second doped segment is insulated from the second doped layer and the second connecting layer, respectively; and the second doped segment is insulated from the first doped segment and the fourth doped segment, respectively.

[0118] Furthermore, the third doped segment is insulated from the second doped layer and the second interconnecting layer, and is also insulated from the first doped segment and the fourth doped segment.

[0119] Furthermore, the fourth doped segment is insulated from the first doped layer and the first connecting layer, and is also insulated from the third doped segment and the second doped segment.

[0120] Example 5

[0121] This embodiment provides a battery assembly, such as Figure 7 As shown, it includes:

[0122] A silicon substrate having opposing first and second surfaces, the first surface having opposing first and second edges along a first direction, and opposing third and fourth edges along a second direction, the second direction intersecting the first direction; the first surface including an edge region and a middle region, the edge region surrounding the middle region;

[0123] A plurality of first doped layers, a plurality of second doped layers, a plurality of first connecting layers, and a plurality of second connecting layers are disposed on the intermediate region. The plurality of first doped layers and the plurality of second doped layers are arranged alternately along a first direction and extend discontinuously along a second direction. The plurality of first connecting layers and the plurality of second connecting layers are arranged alternately along the second direction and extend along the first direction. The first doped layers are connected to the first connecting layers and disconnected at the second connecting layers. The second doped layers are connected to the second connecting layers and disconnected at the first connecting layers. The doping types of the first doped layers and the second doped layers are opposite.

[0124] A third doped layer is disposed on the edge region. The third doped layer includes a first doped segment, a fourth doped segment, a second doped segment, and a third doped segment arranged sequentially in a clockwise direction. The first doped segment is disposed at the first edge and extends continuously in the second direction. The second doped segment is disposed at the second edge and extends continuously in the second direction. The third doped segment is disposed at the third edge and extends continuously in the first direction. The fourth doped segment is disposed at the fourth edge and extends continuously in the first direction. Any two of the first, second, third, and fourth doped segments are P-type doped, and the other two are N-type doped.

[0125] Specifically, the first doping segment is P-type doped, the second doping segment is N-type doped, the third doping segment is P-type doped, the fourth doping segment is N-type doped, the first doped layer and the first connecting layer are P-type doped, and the second doped layer and the second connecting layer are N-type doped.

[0126] Furthermore, doped segments or doped layers with the same doping type are connected together, while doped segments or doped layers with different doping types are insulated from each other.

[0127] That is, the first doped segment is connected to the third doped segment, and the second doped segment is connected to the fourth doped segment; the first doped segment is connected to the end of the first connecting layer, and the second doped segment is connected to the end of the second connecting layer; the third doped segment is connected to the end of the first doped layer, and the fourth doped segment is connected to the end of the second doped layer.

[0128] Furthermore, the first doped segment is insulated from the second doped layer and the second connecting layer, respectively, and the first doped segment is insulated from the fourth doped segment and the second doped segment, respectively.

[0129] Furthermore, the second doped segment is insulated from the first doped layer and the first connecting layer, respectively; and the second doped segment is insulated from the first doped segment and the third doped segment, respectively.

[0130] Furthermore, the third doped segment is insulated from the second doped layer and the second interconnecting layer, and the third doped segment is insulated from the second doped segment and the fourth doped segment.

[0131] Furthermore, the fourth doped segment is insulated from the first doped layer and the first connecting layer, and is also insulated from the third doped segment and the first doped segment.

[0132] Example 6

[0133] This embodiment provides a battery assembly, such as Figure 8 As shown, it includes:

[0134] A silicon substrate having opposing first and second surfaces, the first surface having opposing first and second edges along a first direction, and opposing third and fourth edges along a second direction, the second direction intersecting the first direction; the first surface including an edge region and a middle region, the edge region surrounding the middle region;

[0135] A plurality of first doped layers, a plurality of second doped layers, a plurality of first connecting layers, and a plurality of second connecting layers are disposed on the intermediate region. The plurality of first doped layers and the plurality of second doped layers are arranged alternately along a first direction and extend discontinuously along a second direction. The plurality of first connecting layers and the plurality of second connecting layers are arranged alternately along the second direction and extend along the first direction. The first doped layers are connected to the first connecting layers and disconnected at the second connecting layers. The second doped layers are connected to the second connecting layers and disconnected at the first connecting layers. The doping types of the first doped layers and the second doped layers are opposite.

[0136] A third doped layer is disposed on the edge region. The third doped layer includes a first doped segment, a fourth doped segment, a second doped segment, and a third doped segment arranged sequentially in a clockwise direction. The first doped segment is disposed at the first edge and extends continuously in the second direction. The second doped segment is disposed at the second edge and extends continuously in the second direction. The third doped segment is disposed at the third edge and extends continuously in the first direction. The fourth doped segment is disposed at the fourth edge and extends continuously in the first direction. Any two of the first, second, third, and fourth doped segments are P-type doped, and the other two are N-type doped.

[0137] Specifically, the first doping segment is N-type doped, the second doping segment is P-type doped, the third doping segment is N-type doped, the fourth doping segment is P-type doped, the first doped layer and the first connecting layer are P-type doped, and the second doped layer and the second connecting layer are N-type doped.

[0138] Furthermore, doped segments or doped layers with the same doping type are connected together, while doped segments or doped layers with different doping types are insulated from each other.

[0139] That is, the first doped segment is connected to the fourth doped segment, and the second doped segment is connected to the third doped segment; the first doped segment is connected to the end of the second connecting layer, and the second doped segment is connected to the end of the first connecting layer; the third doped segment is connected to the end of the first doped layer, and the fourth doped segment is connected to the end of the second doped layer.

[0140] Furthermore, the first doped segment is insulated from the first doped layer and the first connecting layer, and the first doped segment is insulated from the third doped segment and the second doped segment, respectively.

[0141] Furthermore, the second doped segment is insulated from the second doped layer and the second connecting layer, respectively; and the second doped segment is insulated from the first doped segment and the fourth doped segment, respectively.

[0142] Furthermore, the third doped segment is insulated from the second doped layer and the second interconnecting layer, and is also insulated from the first doped segment and the fourth doped segment.

[0143] Furthermore, the fourth doped segment is insulated from the first doped layer and the first connecting layer, and is also insulated from the third doped segment and the second doped segment.

[0144] In the description of this specification, the references to terms such as "some embodiments," "illustrative embodiments," "examples," "specific examples," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with an embodiment or example is included in at least one embodiment or example of this application. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0145] The above-disclosed embodiment is merely a preferred embodiment of the present utility model and should not be construed as limiting the scope of the present utility model. Therefore, any equivalent variations made in accordance with the claims of the present utility model shall still fall within the scope of the present utility model.

Claims

1. A back contact cell, characterized in that, include: A silicon substrate having opposing first and second surfaces, the first surface having opposing first and second edges along a first direction, and opposing third and fourth edges along a second direction, the second direction intersecting the first direction; the first surface including an edge region and a middle region, the edge region surrounding the middle region; A third doped layer is disposed on the edge region. The third doped layer includes a first doped segment, a fourth doped segment, a second doped segment, and a third doped segment arranged sequentially in a clockwise direction. The first doped segment is disposed at the first edge and extends continuously along the second direction. The second doped segment is disposed at the second edge and extends continuously along the second direction. The third doped segment is disposed at the third edge and extends continuously along the first direction. The fourth doped segment is disposed at the fourth edge and extends continuously along the first direction. Any two of the first, second, third, and fourth doped segments are P-type doped, and the other two are N-type doped.

2. The back contact cell of claim 1, wherein, The first doping segment is P-type doped, the second doping segment is P-type doped, the third doping segment is N-type doped, and the fourth doping segment is N-type doped. or The first doping segment is N-type doped, the second doping segment is N-type doped, the third doping segment is P-type doped, and the fourth doping segment is P-type doped. or The first doping segment is P-type doped, the second doping segment is N-type doped, the third doping segment is N-type doped, and the fourth doping segment is P-type doped; or The first doping segment is N-type doped, the second doping segment is P-type doped, the third doping segment is P-type doped, and the fourth doping segment is N-type doped; or The first doping segment is P-type doped, the second doping segment is N-type doped, the third doping segment is P-type doped, and the fourth doping segment is N-type doped; or The first doping segment is N-type doped, the second doping segment is P-type doped, the third doping segment is N-type doped, and the fourth doping segment is P-type doped.

3. The back contact battery as described in claim 1, characterized in that, The back contact battery further includes a plurality of first doped layers, a plurality of second doped layers, a plurality of first connecting layers, and a plurality of second connecting layers disposed on the intermediate region. The plurality of first doped layers and the plurality of second doped layers are arranged alternately along the first direction and extend intermittently along the second direction. The plurality of first connecting layers and the plurality of second connecting layers are arranged alternately along the second direction and extend along the first direction. The first doped layer is connected to the first connecting layer and disconnected at the second connecting layer. The second doped layer is connected to the second connecting layer and disconnected at the first connecting layer. The doping types of the first doped layer and the second doped layer are opposite.

4. The back contact cell of claim 3, wherein, The first doping segment is P-type doped, the second doping segment is P-type doped, the third doping segment is N-type doped, the fourth doping segment is N-type doped, the first doped layer and the first connecting layer are P-type doped, and the second doped layer and the second connecting layer are N-type doped; The first doped segment is connected to the end of the first connecting layer, and the second doped segment is connected to the end of the first connecting layer; The third doped segment is connected to the end of the second doped layer, and the fourth doped segment is connected to the end of the second doped layer.

5. The back contact cell of claim 3, wherein, The first doping segment is N-type doped, the second doping segment is N-type doped, the third doping segment is P-type doped, the fourth doping segment is P-type doped, the first doped layer and the first connecting layer are P-type doped, and the second doped layer and the second connecting layer are N-type doped; The first doped segment is connected to the end of the second connecting layer, and the second doped segment is connected to the end of the second connecting layer; The third doped segment is connected to the end of the first doped layer, and the fourth doped segment is connected to the end of the first doped layer.

6. The back contact cell of claim 3, wherein, The first doping segment is P-type doped, the second doping segment is N-type doped, the third doping segment is N-type doped, the fourth doping segment is P-type doped, the first doping layer and the first connecting layer are P-type doped, and the second doping layer and the second connecting layer are N-type doped; The first doped segment is connected to the fourth doped segment, and the second doped segment is connected to the third doped segment; The first doped segment is connected to the end of the first connecting layer, and the second doped segment is connected to the end of the second connecting layer; The third doped segment is connected to the end of the second doped layer, and the fourth doped segment is connected to the end of the first doped layer.

7. The back contact cell of claim 3, wherein, The first doping segment is N-type doped, the second doping segment is P-type doped, the third doping segment is P-type doped, the fourth doping segment is N-type doped, the first doping layer and the first connecting layer are P-type doped, and the second doping layer and the second connecting layer are N-type doped; The first doped segment is connected to the fourth doped segment, and the second doped segment is connected to the third doped segment; The first doped segment is connected to the end of the second connecting layer, and the second doped segment is connected to the end of the first connecting layer; The third doped segment is connected to the end of the first doped layer, and the fourth doped segment is connected to the end of the second doped layer.

8. The back contact cell of claim 3, wherein, The first doping segment is P-type doped, the second doping segment is N-type doped, the third doping segment is P-type doped, the fourth doping segment is N-type doped, the first doping layer and the first connecting layer are P-type doped, and the second doping layer and the second connecting layer are N-type doped; The first doped segment is connected to the third doped segment, and the second doped segment is connected to the fourth doped segment; The first doped segment is connected to the end of the first connecting layer, and the second doped segment is connected to the end of the second connecting layer; The third doped segment is connected to the end of the first doped layer, and the fourth doped segment is connected to the end of the second doped layer.

9. The back contact cell of claim 3, wherein, The first doping segment is N-type doped, the second doping segment is P-type doped, the third doping segment is N-type doped, the fourth doping segment is P-type doped, the first doped layer and the first connecting layer are P-type doped, and the second doped layer and the second connecting layer are N-type doped; The first doped segment is connected to the fourth doped segment, and the second doped segment is connected to the third doped segment; The first doped segment is connected to the end of the second connecting layer, and the second doped segment is connected to the end of the first connecting layer; The third doped segment is connected to the end of the first doped layer, and the fourth doped segment is connected to the end of the second doped layer.

10. A battery assembly characterized by, It includes several back contact batteries as described in any one of claims 1 to 9.

11. A photovoltaic system characterized by, Includes the battery assembly as described in claim 10.

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