Back contact cell and back contact cell assembly

Abstract

The invention discloses a back contact battery and a back contact battery assembly, and the battery comprises a substrate which is provided with a first doping type, the substrate is provided with a first surface, and the first surface is provided with a first side and a second side which are opposite to each other; the first doped regions are located on the side, provided with the first surface, of the substrate and arranged at intervals in the first direction, the first direction is the direction from the first edge to the second edge, the first doped regions are of the second doping type, and the doped regions closest to the first edge and / or the second edge are the first doped regions; and the second doped region is located between any adjacent first doped regions and forms an interdigital structure with the adjacent first doped regions. Wherein the first edge and the second edge of the substrate are provided with at least part of the first doped region, the doping type of the first doped region is opposite to that of the substrate, and a PN junction structure is formed at the edge region of the back contact cell, so that the edge region can be effectively prevented from being compounded, and the efficiency of the back contact cell is improved.

Description

Technical Field

[0001] The present application relates to the technical field of solar cells, and in particular to a back-contact cell and a back-contact cell assembly. Background Art

[0002] Solar energy is a sustainable source of clean energy. Solar cells can convert solar energy into electrical energy by using the photovoltaic effect of semiconductor pn junctions. Currently, solar cells are semiconductor devices that directly convert the energy of sunlight into electrical energy. Solar cells use the photovoltaic effect to excite electrons by absorbing photons and conduct these electrons to generate current through a built-in electric field. However, solar cells have edge recombination at the edges or at the edges of the slice area. Summary of the invention

[0003] The present application provides a back-contact battery and a back-contact battery assembly to solve the problem of low battery efficiency due to edge recombination at the edges of the back-contact battery in the related art.

[0004] According to one aspect of the present application, a back-contact battery is provided, comprising: a substrate having a first doping type, the substrate having a first surface, the first surface having a first edge and a second edge relative to each other; first doping regions, located on a side of the substrate having the first surface, and arranged at intervals along a first direction, the first direction being the direction from the first edge to the second edge, the first doping regions having a second doping type, and the doping region closest to the first edge and / or the second edge is the first doping region; and second doping regions, located between any adjacent first doping regions, and forming an interdigitated structure with adjacent first doping regions.

[0005] Optionally, the first surface also has a third side and a fourth side relative to each other, the first doped region has a plurality of first finger portions extending along the first direction, the first finger portions among the plurality of first finger portions closest to the third side and the fourth side have a first width in the second direction, the first finger portions other than the first finger portions closest to the third side and the fourth side have a second width in the second direction, the second direction is perpendicular to the first direction and parallel to the first surface, and the first width is greater than the second width.

[0006] Optionally, the back-contact battery further includes at least one isolation region, which isolates the back-contact battery into at least two parts, and the isolation region extends along the first direction. The first finger portion closest to the isolation region among the plurality of first finger portions has a third width in the second direction, and the third width is greater than the second width. The isolation region is a non-doped region.

[0007] Optionally, the isolation region has a fourth width in the second direction, a non-doped region is provided between the first doped region and the second doped region, the non-doped region has a fifth width in the second direction, and the fourth width is greater than the fifth width.

[0008] Optionally, the back contact battery further comprises a plurality of gate lines, wherein the gate lines connect a plurality of the first doping regions or connect a plurality of the second doping regions, and an extension direction of the gate lines is the same as an extension direction of the isolation region.

[0009] Optionally, the first width includes 200 μm to 1500 μm, and / or the second width includes 150 μm to 800 μm, and / or the third width includes 200 μm to 1500 μm, and / or the fourth width includes 100 μm to 1000 μm, and / or the fifth width includes 5 μm to 500 μm.

[0010] According to another aspect of the present application, a back-contact battery assembly is provided, comprising at least one back-contact battery as described above.

[0011] The back contact battery of the present application includes a substrate, a first doping region and a second doping region, wherein the first doping regions are arranged at intervals on the first surface of the substrate in a direction from the first edge to the second edge, the second doping region is located between adjacent first doping regions, and parts of the first doping region and the second doping region cross each other to form an interdigitated structure, wherein at least part of the first doping region is provided at the first edge and the second edge of the substrate, the first doping region and the substrate have opposite doping types, and a PN junction structure is formed at the edge region of the back contact battery, which can effectively prevent the edge region from being recombined, and improve the efficiency of the back contact battery. The problem of low battery efficiency due to edge recombination at the edge of the back contact battery in the related art is solved. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] The drawings constituting a part of the present application are used to provide a further understanding of the present application. The illustrative embodiments and descriptions of the present application are used to explain the present application and do not constitute an improper limitation on the present application. In the drawings:

[0013] Figure 1 A schematic structural diagram of a back contact battery provided in an embodiment of the present application is shown;

[0014] Figure 2 A schematic structural diagram of another back contact battery provided in an embodiment of the present application is shown;

[0015] Figure 3 A schematic structural diagram of another back-contact battery provided in an embodiment of the present application is shown.

[0016] The above drawings include the following reference numerals:

[0017] 10. substrate; 20. first doped region; 21. first interdigital portion; 30. second doped region; 31. second interdigital portion; 40. isolation region. DETAILED DESCRIPTION

[0018] It should be noted that, in the absence of conflict, the embodiments and features in the embodiments of the present application can be combined with each other. The present application will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0019] In order to enable those skilled in the art to better understand the solution of the present application, the technical solution in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the present application.

[0020] It should be noted that the terms "first", "second", etc. in the specification and claims of the present application and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequential order. It should be understood that the data used in this way can be interchanged where appropriate, so that the embodiments of the present application described here. In addition, the terms "including" and "having" and any of their variations are intended to cover non-exclusive inclusions, for example, a process, method, system, product or device comprising a series of steps or units is not necessarily limited to those steps or units clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0021] As mentioned in the background technology, solar cells are semiconductor devices that convert sunlight energy directly into electrical energy. Solar cells use the photovoltaic effect to excite electrons by absorbing photons and conduct these electrons to generate current through a built-in electric field, but solar cells have edge recombination at the edge or at the edge of the slice area.

[0022] According to one aspect of the present application, Figure 1As shown, a back contact battery is provided, comprising: a substrate 10 having a first doping type, the substrate 10 having a first surface, the first surface having a first edge and a second edge opposite to each other; first doping regions 20, located on a side of the substrate 10 having the first surface, and arranged at intervals along a first direction X, the first direction X being the direction from the first edge to the second edge, the first doping regions 20 having a second doping type, and the doping region closest to the first edge and / or the second edge is the first doping region 20; and second doping regions 30, located between any adjacent first doping regions 20, and forming an interdigitated structure with the adjacent first doping regions 20.

[0023] By providing at least a portion of the first doped region at the first side and the second side of the substrate, the first doped region and the substrate have opposite doping types, and forming a PN junction structure at the edge region of the back contact battery, it is possible to effectively prevent the edge region from being recombined, thereby improving the efficiency of the back contact battery. This solves the problem of low battery efficiency due to edge recombination at the edge of the back contact battery in the related art.

[0024] In some optional embodiments, such as Figure 2 As shown, the first surface further has a third side and a fourth side relative to each other, the first doping region 20 has a plurality of first interdigitated portions 21 extending along the first direction X, the first interdigitated portions 21 closest to the third side and the fourth side among the plurality of first interdigitated portions 21 have a first width L1 in the second direction Y, and the first interdigitated portions 21 other than the first interdigitated portions 21 closest to the third side and the fourth side have a second width L2 in the second direction Y, the second direction Y is perpendicular to the first direction X and parallel to the first surface, and the first width L1 is greater than the second width L2.

[0025] In the above optional implementation, if Figure 2 As shown, the second direction Y from the third side to the fourth side is as shown in Figure 2 As shown, the first doping region 20 has a plurality of first interdigitated portions 21 along the first direction X, and the plurality of first interdigitated portions 21 are arranged along the second direction Y. The width of the first interdigitated portions 21 closest to the third side and the fourth side is the second width L1, and the other first interdigitated portions 21 except the first interdigitated portions 21 closest to the third side and the fourth side have a first width L2. Setting the second width L2 to be smaller than the first width L1 can increase the probability of collecting carriers at the edge of the back contact battery, while increasing the component end alignment margin.

[0026] In the above optional implementation, if Figure 2As shown, the second doping region 30 has a plurality of second interdigital portions 31 along the first direction X, and the first interdigital portions 21 and the second interdigital portions 31 cross each other in the second direction to form an interdigital structure.

[0027] In some optional embodiments, such as Figure 3 As shown, the back contact battery further includes at least one isolation region 40, which isolates the back contact battery into at least two parts. The isolation region 40 extends along the first direction X, and the first interdigitated portion closest to the isolation region 40 among the plurality of first interdigitated portions has a third width L3 in the second direction Y, and the third width L3 is greater than the second width L2, and the isolation region 40 is a non-doped region.

[0028] In the above optional implementation, if Figure 3 As shown, in the preparation of a back-contact battery, it is sometimes necessary to slice a whole battery to divide the whole battery into multiple parts. The area used for scribing is the isolation area 40. The first finger portion closest to the isolation area 40 has a third width L3 in the second direction Y. The third width L3 is greater than the second width L2, which can increase the probability of collecting carriers at the edge of the back-contact battery and increase the component end alignment margin.

[0029] In some optional embodiments, such as Figure 3 As shown, the isolation region 40 has a fourth width L4 in the second direction Y, a non-doped region is provided between the first doping region 20 and the second doping region 30, the non-doped region has a fifth width L5 in the second direction Y, and the fourth width L4 is greater than the fifth width L5.

[0030] In the above optional implementation, if Figure 3 As shown, there is a spacing region between the first doping region 20 and the second doping region 30 as a non-doping region, the width of the non-doping region in the second direction Y is the fifth width L5, and the width of the isolation region 40 in the second direction Y is the fourth width L4, wherein the fourth width L4 is greater than the fifth width L5. The isolation region 40 can avoid the influence of the battery cut in half on the doping region, and the isolation region 40 can play a transmission barrier role, reducing the influence of the recombination of the cutting region; at the same time, the fourth region width L4> the fifth region width, which can effectively increase the cutting alignment process window. Figure 2 and Figure 3 The base 10 and Figure 1 The description in is consistent.

[0031] In some optional embodiments, the back-contact battery further comprises a plurality of gate lines, the gate lines connect the plurality of first doping regions or connect the plurality of second doping regions, and the extension direction of the gate lines is the same as the extension direction of the isolation regions.

[0032] In the above optional implementation, the consistency of the isolation area of ​​the back contact battery and the extension direction of the grid line helps to distribute the current more evenly on the battery cell, reduces the phenomenon of current crowding, and makes the current evenly distributed, thereby improving the current collection efficiency. Due to the reduction of resistance and current crowding, the energy conversion efficiency can be optimized, so that the photovoltaic module can more effectively convert solar energy into electrical energy, and the current can pass through the grid line more smoothly, reducing resistance, so that the photoelectric conversion efficiency is improved. The uniform distribution of current helps to reduce hot spots and local overheating, thereby protecting the battery cell from damage and enhancing the long-term stability and reliability of the photovoltaic module. It can also improve the reliability of the photovoltaic module. The uniform distribution of current can reduce the phenomenon of hot spots and local overheating, thereby extending the service life of the photovoltaic module.

[0033] The technical solution of the present application can realize offline or online rapid tunneling resistance test and analysis of solar cells, and can be used for full back electrode contact cells with main grid-free technology (0BB, Zero Busbar) or multi-main grid technology (MBB, MULTI-BUSBAR), full back electrode contact cells including (IBC, Interdigitated back contact), full back contact cells (ABC, Allback contact), composite passivated back contact cells (HPBC, Hybrid Passivated back contact), emitter back passivated cells (PERC, Passivated Emitter and Rear Cell), tunneling oxide passivated contact cells (TOPcon, Tnuuel Oxide Passivated contact), TOPcon-IBC cells, crystalline silicon heterojunction solar cells (HJT, Heterojunction with Intrinsic Thin-layer), perovskite stacked cells, flexible cells and other photovoltaic cells. The tunneling resistance or other arbitrary thin layer resistance test.

[0034] In some optional embodiments, the first width includes 200 μm to 1500 μm, and / or the second width includes 150 μm to 800 μm, and / or the third width includes 200 μm to 1500 μm, and / or the fourth width includes 100 μm to 1000 μm, and / or the fifth width includes 5 μm to 500 μm.

[0035] In the above optional embodiment, setting the above first width, the above second width, the above third width, the above fourth width and the above fifth width within the above numerical range can effectively increase the collection probability of edge carriers of the back contact battery and increase the component end alignment margin.

[0036] According to another aspect of the present application, a back-contact battery assembly is provided, comprising at least one of the above-mentioned back-contact batteries.

[0037] The back contact battery assembly of the present application includes at least one back contact battery, which has at least part of the first doping region at the first side and the second side of the substrate, and the doping type of the first doping region and the substrate are opposite, and a PN junction structure is formed at the edge area of ​​the back contact battery, which can effectively prevent the edge area from being recombined and improve the efficiency of the back contact battery. The problem of low battery efficiency due to edge recombination at the edge of the back contact battery in the related art is solved.

[0038] The above-mentioned back contact battery of the present application will be specifically described below in combination with specific embodiments and comparative examples.

[0039] Example 1

[0040] The present application provides a back contact battery, comprising:

[0041] A substrate, wherein the substrate is made of silicon, the doping type is N-type, and the thickness is 120 μm;

[0042] a first doping region, comprising a plurality of first interdigital portions extending along the first direction, wherein the first interdigital portions closest to the third side and the fourth side among the plurality of first interdigital portions have a first width in the second direction, and the first interdigital portions other than the first interdigital portions closest to the third side and the fourth side have a second width in the second direction, the second direction is perpendicular to the first direction and parallel to the first surface, the first width is greater than the second width, the doping type of the first doping region is P type, the first width is 200 μm, and the second width is 150 μm;

[0043] A second doping region is located between any adjacent first doping regions, and forms an interdigitated structure with the adjacent first doping regions, and the doping type of the second doping region is N type;

[0044] An isolation region, dividing the substrate into at least two regions, wherein the width of the first doping region closest to the isolation region is a third width, the third width is greater than the second width, and the third width is 200 μm;

[0045] The isolation region has a fourth width in the second direction, a non-doped region is provided between the first doped region and the second doped region, the width of the non-doped region in the second direction is the fifth width, the fourth width is greater than the fifth width, the fourth width is 100 μm, and the fifth width is 5 μm.

[0046] Example 2

[0047] The present application provides a back contact battery, comprising:

[0048] A substrate, wherein the substrate is made of silicon, the doping type is N-type, and the thickness is 120 μm;

[0049] a first doping region, comprising a plurality of first interdigital portions extending along the first direction, wherein the first interdigital portions closest to the third side and the fourth side among the plurality of first interdigital portions have a first width in the second direction, and the first interdigital portions other than the first interdigital portions closest to the third side and the fourth side have a second width in the second direction, the second direction is perpendicular to the first direction and parallel to the first surface, the first width is greater than the second width, the doping type of the first doping region is P type, the first width is 800 μm, and the second width is 500 μm;

[0050] A second doping region is located between any adjacent first doping regions, and forms an interdigitated structure with the adjacent first doping regions, and the doping type of the second doping region is N type;

[0051] An isolation region, dividing the substrate into at least two regions, wherein the width of the first doping region closest to the isolation region is a third width, the third width is greater than the second width, and the third width is 800 μm;

[0052] The isolation region has a fourth width in the second direction, a non-doped region is provided between the first doped region and the second doped region, the width of the non-doped region in the second direction is the fifth width, the fourth width is greater than the fifth width, the fourth width is 500 μm, and the fifth width is 250 μm.

[0053] Example 3

[0054] The present application provides a back contact battery, comprising:

[0055] A substrate, wherein the substrate is made of silicon, the doping type is N-type, and the thickness is 120 μm;

[0056] a first doping region, comprising a plurality of first interdigital portions extending along the first direction, wherein the first interdigital portions closest to the third side and the fourth side among the plurality of first interdigital portions have a first width in the second direction, and the first interdigital portions other than the first interdigital portions closest to the third side and the fourth side have a second width in the second direction, the second direction is perpendicular to the first direction and parallel to the first surface, the first width is greater than the second width, the doping type of the first doping region is P type, the first width is 1500 μm, and the second width is 800 μm;

[0057] A second doping region is located between any adjacent first doping regions, and forms an interdigitated structure with the adjacent first doping regions, and the doping type of the second doping region is N type;

[0058] An isolation region, dividing the substrate into at least two regions, wherein the width of the first doping region closest to the isolation region is a third width, the third width is greater than the second width, and the third width is 1500 μm;

[0059] The isolation region has a fourth width in the second direction, a non-doped region is provided between the first doped region and the second doped region, the width of the non-doped region in the second direction is the fifth width, the fourth width is greater than the fifth width, the fourth width is 1000 μm, and the fifth width is 500 μm.

[0060] Comparative Example 1

[0061] The present application provides a back contact battery, comprising:

[0062] A substrate, wherein the substrate is made of silicon, the doping type is N-type, and the thickness is 120 μm;

[0063] a first doping region, comprising a plurality of first interdigital portions extending along the first direction, wherein the first interdigital portions closest to the third side and the fourth side among the plurality of first interdigital portions have a first width in the second direction, and the first interdigital portions other than the first interdigital portions closest to the third side and the fourth side have a second width in the second direction, the second direction is perpendicular to the first direction and parallel to the first surface, the first width is greater than the second width, the doping type of the first doping region is N type, the first width is 200 μm, and the second width is 150 μm;

[0064] A second doping region is located between any adjacent first doping regions, and forms an interdigitated structure with the adjacent first doping regions, and the doping type of the second doping region is P type;

[0065] An isolation region, dividing the substrate into at least two regions, wherein the width of the first doping region closest to the isolation region is a third width, the third width is greater than the second width, and the third width is 200 μm;

[0066] The isolation region has a fourth width in the second direction, a non-doped region is provided between the first doped region and the second doped region, the width of the non-doped region in the second direction is the fifth width, the fourth width is greater than the fifth width, the fourth width is 100 μm, and the fifth width is 5 μm.

[0067] Comparative Example 2

[0068] The present application provides a back contact battery, comprising:

[0069] A substrate, wherein the substrate is made of silicon, the doping type is N-type, and the thickness is 120 μm;

[0070] a first doping region, comprising a plurality of first interdigitated portions extending along the first direction, wherein the first interdigitated portions closest to the third side and the fourth side among the plurality of first interdigitated portions have a first width in the second direction, and the first interdigitated portions other than the first interdigitated portions closest to the third side and the fourth side have a second width in the second direction, the second direction is perpendicular to the first direction and parallel to the first surface, the first width is smaller than the second width, the doping type of the first doping region is P type, the first width is 200 μm, and the second width is 280 μm;

[0071] A second doping region is located between any adjacent first doping regions, and forms an interdigitated structure with the adjacent first doping regions, and the doping type of the second doping region is N type;

[0072] An isolation region, dividing the substrate into at least two regions, wherein the width of the first doping region closest to the isolation region is a third width, the third width is smaller than the second width, and the third width is 220 μm;

[0073] The isolation region has a fourth width in the second direction, a non-doped region is provided between the first doped region and the second doped region, the width of the non-doped region in the second direction is the fifth width, the fourth width is greater than the fifth width, the fourth width is 100 μm, and the fifth width is 10 μm.

[0074] Comparative Example 3

[0075] The present application provides a back contact battery, comprising:

[0076] A substrate, wherein the substrate is made of silicon, the doping type is N-type, and the thickness is 120 μm;

[0077] a first doping region, comprising a plurality of first interdigital portions extending along the first direction, wherein the first interdigital portions closest to the third side and the fourth side among the plurality of first interdigital portions have a first width in the second direction, and the first interdigital portions other than the first interdigital portions closest to the third side and the fourth side have a second width in the second direction, the second direction is perpendicular to the first direction and parallel to the first surface, the first width is greater than the second width, the doping type of the first doping region is P type, the first width is 100 μm, and the second width is 100 μm;

[0078] A second doping region is located between any adjacent first doping regions, and forms an interdigitated structure with the adjacent first doping regions, and the doping type of the second doping region is N type;

[0079] An isolation region, dividing the substrate into at least two regions, wherein the width of the first doping region closest to the isolation region is a third width, the third width is greater than the second width, and the third width is 150 μm;

[0080] The isolation region has a fourth width in the second direction, a non-doped region is provided between the first doped region and the second doped region, the width of the non-doped region in the second direction is the fifth width, the fourth width is greater than the fifth width, the fourth width is 80 μm, and the fifth width is 3 μm.

[0081] Comparative Example 4

[0082] The present application provides a back contact battery, comprising:

[0083] A substrate, wherein the substrate is made of silicon, the doping type is N-type, and the thickness is 120 μm;

[0084] a first doping region, comprising a plurality of first interdigital portions extending along the first direction, wherein the first interdigital portions closest to the third side and the fourth side among the plurality of first interdigital portions have a first width in the second direction, and the first interdigital portions other than the first interdigital portions closest to the third side and the fourth side have a second width in the second direction, the second direction is perpendicular to the first direction and parallel to the first surface, the first width is greater than the second width, the doping type of the first doping region is P type, the first width is 1800 μm, and the second width is 1000 μm;

[0085] A second doping region is located between any adjacent first doping regions, and forms an interdigitated structure with the adjacent first doping regions, and the doping type of the second doping region is N type;

[0086] An isolation region, dividing the substrate into at least two regions, wherein the width of the first doping region closest to the isolation region is a third width, the third width is greater than the second width, and the third width is 1800 μm;

[0087] The isolation region has a fourth width in the second direction, a non-doped region is provided between the first doped region and the second doped region, the width of the non-doped region in the second direction is the fifth width, the fourth width is greater than the fifth width, the fourth width is 1200 μm, and the fifth width is 800 μm.

[0088] The performance of the back contact cells in the above-mentioned Examples 1 to 3 and Comparative Examples 1 to 4 was tested, and the test results are as follows:

[0089] Table 1

[0090] Battery efficiency Example 1 27.52％ Example 2 27.55％ Example 3 27.53％ Comparative Example 1 27.44％ Comparative Example 2 27.45％ Comparative Example 3 27.41％ Comparative Example 4 27.43％

[0091] It can be seen from Example 1, Example 2, Example 3 and Comparative Example 1 in the above table that the doping type of the first doping region is set to be opposite to the doping type of the silicon substrate, which can improve the battery efficiency. It can be seen from Example 1, Example 2, Example 3 and Comparative Example 2 in the above table that the first width is set to be greater than the second width, and the third width is set to be greater than the second width, which can also improve the battery efficiency. It can be seen from Example 1, Example 2, Example 3 and Comparative Example 3 and Comparative Example 4 in the above table that the battery efficiency can also be improved by setting the first to fifth widths within a reasonable range.

[0092] It should also be noted that the terms "include", "comprises" or any other variations thereof are intended to cover non-exclusive inclusion, so that a process, method, commodity or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, commodity or device. In the absence of more restrictions, the elements defined by the sentence "comprises a ..." do not exclude the existence of other identical elements in the process, method, commodity or device including the elements.

[0093] From the above description, it can be seen that the above embodiments of the present application achieve the following technical effects:

[0094] 1) The back contact cell of the present application has at least part of the first doped region at the first side and the second side of the substrate, and the doping type of the first doped region and the substrate are opposite, and a PN junction structure is formed at the edge area of ​​the back contact cell, which can effectively prevent the edge area from being recombined, and improve the efficiency of the back contact cell. This solves the problem of low cell efficiency due to edge recombination at the edge of the back contact cell in the related art.

[0095] 2) The isolation area in the back contact cell of the present application can avoid the influence of silicon wafer cutting in half on the doped area, and can also play a transmission barrier role, reducing the influence of recombination in the cutting area; at the same time, the fourth width L4> the fifth width L5, which can effectively increase the cutting alignment process window. The first width L1> the second width L2, the third width L3> the second width L2, can increase the probability of collecting carriers at the edge of the back contact cell, and at the same time increase the alignment margin of the component end.

[0096] The above are only preferred embodiments of the present application and are not intended to limit the present application. For those skilled in the art, the present application may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. 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: The following steps are involved: A substrate having a first doping type, the substrate having a first surface, the first surface having first and second opposite sides; first doping regions, located on a side of the substrate having the first surface, and arranged at intervals along a first direction, the first direction being a direction from the first side to the second side, the first doping regions having a second doping type, and the doping region closest to the first side and / or the second side is the first doping region; The second doping region is located between any adjacent first doping regions and forms an interdigitated structure with the adjacent first doping regions.

2. The back contact cell according to claim 1, characterized in that: The first surface also has a third side and a fourth side opposite to each other, the first doped region has a plurality of first interdigitated portions extending along the first direction, the first interdigitated portions among the plurality of first interdigitated portions being closest to the third side and the fourth side have a first width in the second direction, the first interdigitated portions other than the first interdigitated portions being closest to the third side and the fourth side have a second width in the second direction, the second direction is perpendicular to the first direction and parallel to the first surface, and the first width is greater than the second width.

3. The back contact battery according to claim 2, characterized in that: The back-contact battery also includes at least one isolation region, which isolates the back-contact battery into at least two parts, and the isolation region extends along the first direction. The first finger portion closest to the isolation region among the plurality of first fingers has a third width in the second direction, and the third width is greater than the second width. The isolation region is a non-doped region.

4. The back contact cell according to claim 3, characterized in that: The isolation region has a fourth width in the second direction, a non-doped region is provided between the first doped region and the second doped region, the non-doped region has a fifth width in the second direction, and the fourth width is greater than the fifth width.

5. The back contact battery according to claim 3, characterized in that: The back contact battery further includes a plurality of gate lines, wherein the gate lines connect a plurality of the first doping regions or connect a plurality of the second doping regions, and an extension direction of the gate lines is the same as an extension direction of the isolation region.

6. The back contact cell according to claim 4, characterized in that: The first width includes 200 μm to 1500 μm, and / or The second width includes 150 μm to 800 μm, and / or The third width is 200 μm to 1500 μm, and / or The fourth width includes 100 μm to 1000 μm, and / or The fifth width is in the range of 5 μm to 500 μm.

7. A back contact battery assembly, characterized in that: Comprising at least one back contact cell according to any one of claims 1 to 6.

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