Topcon cells and photovoltaic modules

Abstract

The application relates to the technical field of solar cells, in particular to a TOPCon cell and a photovoltaic module. The TOPCon cell has a front surface and a back surface arranged oppositely, the back surface comprises a continuous split area and a non-split area; wherein the non-split area is provided with a passivation contact structure, and the split area is not provided with the passivation contact structure. The TOPCon cell of the technical scheme can eliminate split damage, the split area is free of the passivation contact structure, physical damage of the back surface passivation contact structure caused by laser splitting can be avoided, passivation loss (pFF drop reduction) and carrier recombination of the fracture surface can be significantly reduced, in addition, crack propagation can be inhibited, the film layer stack of the split area is reduced, local stress is effectively released, and efficiency decay caused by transverse extension of cracks in the mechanical splitting process is prevented.

Description

Technical Field

[0001] This application relates to the field of solar cell technology, and more particularly to a TOPCon cell and photovoltaic module. Background Technology

[0002] In recent years, TOPCon cells have developed very rapidly, with a market share exceeding 60%. Cellular cells can reduce current, thereby effectively reducing heat loss within the module caused by high current and further increasing module power. Photovoltaic module products are mainly represented by half-cell modules and shingled modules; both technologies require cutting a whole cell into cellular segments before connecting them in series and parallel.

[0003] Currently, the mainstream slicing technology uses laser-based non-destructive slicing. Laser-based non-destructive slicing involves precisely controlling heating and localized auxiliary cooling with a laser to create a large temperature gradient in the silicon wafer. This generates thermal stress in the material up to the fracture threshold, initiating cracks. The cracks propagate along the thermal gradient caused by the laser beam path, and finally, mechanical slicing completes the slicing process. To precisely control the crack trajectory, when the laser heats the front side of the cell, an extremely small notch must be machined at each end of the front side, ensuring that fracture propagation begins and ends at the notch. However, the resulting fracture surface exhibits an excessively high recombination rate of charge carriers, significantly impacting cell performance.

[0004] It should be noted that the above content is not necessarily prior art, nor is it intended to limit the scope of patent protection of this application. Utility Model Content

[0005] This application provides a TOPCon battery and photovoltaic module to solve or alleviate one or more of the technical problems mentioned above.

[0006] The first aspect of this application provides a TOPCon battery, which has a front side and a back side disposed opposite to each other. The back side includes a continuously disposed cleaved region and a non-cleaved region. The non-cleaved region has a passivation contact structure, while the cleaved region does not. This first aspect of the application can eliminate cleaving damage. Because the cleaved region lacks a passivation contact structure, physical damage to the passivation contact structure on the back side caused by laser cleaving can be avoided, significantly reducing passivation loss (reducing pFF decrease) and carrier recombination at the fracture surface. Furthermore, it can suppress crack propagation because the reduced film layer stacking in the cleaved region effectively releases local stress and prevents efficiency degradation caused by lateral crack propagation during mechanical cleaving.

[0007] A second aspect of this application provides a photovoltaic module, the photovoltaic module comprising a half-cell, the half-cell being formed by laser non-destructive cleaving of the TOPCon cell described in the first aspect of this application; the photovoltaic module is a half-cell module or a shingled module. Therefore, because the conversion efficiency of a TOPCon cell after cleaving is higher than that of a conventionally cleaved TOPCon cell, the power gain of the half-cell module or shingled module can be enhanced. Attached Figure Description

[0008] In the accompanying drawings, unless otherwise specified, the same reference numerals throughout the various drawings denote the same or similar parts or elements. These drawings are not necessarily drawn to scale. It should be understood that these drawings depict only some embodiments disclosed in this application and should not be construed as limiting the scope of this application.

[0009] Figure 1 This is a schematic diagram of the TOPCon battery provided in the embodiments of this application.

[0010] Explanation of reference numerals in the attached figures: 1-Top electrode; 2-First antireflective coating; 3-First passivation layer; 4-Boron-doped polysilicon; 5-N-type silicon substrate; 6-Tunneling layer; 7-Phosphorus-doped polysilicon; 8-Second passivation layer; 9-Second antireflective coating; 10-Back electrode; 11-Cracked region. Detailed Implementation

[0011] The embodiments of this application are described in detail below, examples of which are illustrated in the accompanying drawings. In the drawings, for clarity, the dimensions of layers, regions, and elements, as well as their relative dimensions, may be exaggerated. Throughout, the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain this application, and should not be construed as limiting this application. It should be noted that, unless otherwise specified, the embodiments and features in the embodiments of this application can be combined with each other.

[0012] It should be understood that when an element or layer is referred to as "on," "adjacent to," "connected to," or "coupled to" other elements or layers, it may be directly on, adjacent to, connected to, or coupled to other elements or layers, or there may be intervening elements or layers. Conversely, when an element is referred to as "directly on," "directly adjacent to," "directly connected to," or "directly coupled to" other elements or layers, there are no intervening elements or layers. It should be understood that although the terms first, second, third, etc., may be used to describe various elements, components, areas, layers, and / or portions, these elements, components, areas, layers, and / or portions should not be limited by these terms. These terms are only used to distinguish one element, component, area, layer, or portion from another element, component, area, layer, or portion. Therefore, without departing from the teachings of this application, the first element, component, area, layer, or portion discussed below may be referred to as a second element, component, area, layer, or portion. And the discussion of a second element, component, area, layer, or portion does not imply that the first element, component, area, layer, or portion necessarily exists in this application.

[0013] In this application, unless otherwise expressly specified and limited, the terms "installation," "connection," "joining," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise expressly limited. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0014] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this application are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such terms can be used interchangeably where appropriate so that the embodiments of this application described herein can be implemented, for example, in orders other than those illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover a non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0015] In this application, when numerical intervals (i.e., numerical ranges) are involved, unless otherwise specified, the distribution of selectable numerical values ​​within the numerical interval is considered continuous, and includes the two endpoints of the numerical interval (i.e., the minimum and maximum values), as well as every numerical value between these two endpoints. Unless otherwise specified, when a numerical interval refers only to integers within that numerical interval, it includes the two endpoint integers of the numerical range, as well as every integer between the two endpoints, which is equivalent to directly listing every integer. When multiple numerical ranges are provided to describe features or characteristics, these numerical ranges can be merged. In other words, unless otherwise specified, the numerical ranges disclosed in this application should be understood to include any and all subranges included therein. The "numerical value" in the numerical interval can be any quantitative value, such as a number, percentage, ratio, etc. The term "numerical interval" can be broadly included to include percentage intervals, ratio intervals, proportion intervals, etc.

[0016] The fill factor (FF) used in this article refers to the actual maximum available power (P). m or V mp ×J mp The ratio of the theoretical (not practically available) power (Jsc × Voc) to the theoretical (not practically available) power (Jsc × Voc). Therefore, FF can be determined by the following formula: FF = (V mp ×J mp ) / (J sc ×V oc Jmp and Vmp represent the current density and voltage at the maximum power point (Pm), respectively, which is obtained by changing the resistance in the circuit until J×V reaches its maximum value; Jsc and Voc represent the short-circuit current and open-circuit voltage, respectively. The fill factor is a key parameter for evaluating solar cells. Commercial solar cells typically have a fill factor of approximately 60% or higher.

[0017] The open-circuit voltage (Voc) used in this paper is the potential difference between the anode and cathode of the device under conditions of no external load connection.

[0018] The short-circuit current density (Jsc) used in this article is the current generated per unit area of ​​solar cell in a short-circuit state under standard test conditions (STC).

[0019] The power conversion efficiency (PCE) of solar cells used in this article refers to the percentage of power converted from absorbed light into electrical energy. The PCE of a solar cell can be measured under standard test conditions (STC) based on incident light irradiance (E: W / m²). 2 ) and the surface area of ​​solar cells (Ac:m 2The STC is calculated by dividing by the point of maximum power (Pm). STC typically refers to the value at a temperature of 25°C and an irradiance of 100 W / m². 2 The spectrum of air quality 1.5 (AM1.5).

[0020] In this article, TOPCon (Tunnel Oxide Passivated Contact) battery refers to a tunnel oxide passivated contact battery.

[0021] This application provides a TOPCon cell and photovoltaic module technical solution. Based on this, the recombination rate of charge carriers on the fracture surface formed after cleaving is reduced, as detailed below.

[0022] Exemplary embodiments according to this application will now be described in more detail with reference to the accompanying drawings. It should be understood that these exemplary embodiments may be implemented in many different forms and should not be construed as being limited to the embodiments set forth herein.

[0023] The first aspect of this application provides a TOPCon battery.

[0024] like Figure 1 As shown, the TOPCon battery has a front and a back side arranged opposite to each other. The back side includes a continuously arranged cleaved region 11 and a non-cleaved region. The non-cleaved region has a passivation contact structure, while the cleaved region does not. In a first aspect, this application's embodiments can eliminate cleaving damage. Because the cleaved region lacks a passivation contact structure, physical damage to the passivation contact structure on the back side caused by laser cleaving can be avoided, significantly reducing passivation loss (reducing pFF decrease) and carrier recombination at the fracture surface. Furthermore, crack propagation can be suppressed because the reduced film layer stacking in the cleaved region effectively releases local stress and prevents efficiency degradation caused by lateral crack propagation during mechanical cleaving.

[0025] In an optional embodiment, in this TOPCon battery, the cleaved region 11 has a first cutting edge and a second cutting edge disposed opposite to each other, and the distance between the first cutting edge and the second cutting edge is 40μm to 500μm. For example, the distance between the first cutting edge and the second cutting edge can be 40μm, 100μm, 200μm, 300μm, 400μm, or 500μm. Thus, the area between the first cutting edge and the second cutting edge is the cleaved region, which can be the area where the laser cleaving split line is located.

[0026] Preferably, the symmetry line of the cleavage region is the splitting line.

[0027] In an optional embodiment, the cross-section of the cleaved region in this TOPCon battery is rectangular. This facilitates fabrication and shaping.

[0028] In an optional embodiment, the passivation contact structure in this TOPCon cell includes a stacked tunneling layer and doped polycrystalline silicon. This allows for good surface passivation and selective carrier transport.

[0029] Furthermore, depending on the substrate type, doped polycrystalline silicon can be phosphorus-doped polycrystalline silicon (n... + -poly-Si) or boron-doped polycrystalline silicon (p + -poly-Si).

[0030] In an optional embodiment, the TOPCon battery may include: The N-type silicon substrate 5 has a front side and a back side disposed opposite to each other, the back side including a continuously disposed cleaving region 11 and a non-cleaving region; thereby facilitating cleaving.

[0031] A tunneling layer 6 is stacked on the non-cracked region of the N-type silicon substrate 5. Thus, the tunneling layer 6, located on the non-cracked region, provides both carrier tunneling and avoids passivation losses in the cracked region 11 caused by the presence of the tunneling layer 6. Optionally, the tunneling layer 6 can be a SiO2 layer, and its thickness can be 1 nm to 2 nm.

[0032] Phosphorus-doped polysilicon 7 is stacked on the side of the tunneling layer 6 away from the N-type silicon substrate 5. Thus, the phosphorus-doped polysilicon 7 is located in the non-cracked region, providing both field passivation and avoiding passivation loss in the cracked region 11 caused by the presence of the phosphorus-doped polysilicon 7. Optionally, the thickness of the phosphorus-doped polysilicon 7 can be 80 nm to 200 nm, for example, 80 nm, 120 nm, 150 nm, 200 nm, etc. This balances passivation and optical loss.

[0033] In an optional embodiment, the TOPCon battery further includes: A second passivation layer 8 is stacked on the side of the phosphorus-doped polysilicon 7 away from the tunneling layer 6, and also stacked on the cleaved region of the N-type silicon substrate 5; thereby enhancing passivation. For example, the second passivation layer 8 is an aluminum oxide layer with a thickness of 1.5 nm to 3 nm.

[0034] A second antireflective film 9 is stacked on the side of the second passivation layer 8 away from the N-type silicon substrate 5. This serves for back-side antireflection and passivation. For example, the second antireflective film 9 is a silicon nitride layer with a thickness of 60 nm to 80 nm.

[0035] A back electrode 10 is provided, one end of which is in contact with the phosphorus-doped polycrystalline silicon 7. This reduces carrier recombination caused by direct contact between the metal and the N-type silicon substrate 5.

[0036] In an optional embodiment, in the TOPCon cell, the front side of the N-type silicon substrate 5 is sequentially stacked with boron-doped polycrystalline silicon 4, a first passivation layer 3, and a first antireflection film 2 in a first direction; the first direction is from the N-type silicon substrate 5 to a direction away from the N-type silicon substrate 5. Thus, the boron-doped polycrystalline silicon 4 is used to form a pn junction on the surface of the N-type silicon substrate 5 to achieve the separation of photogenerated carriers, the first passivation layer 3 is used to passivate the front side, and the first antireflection film 2 is used for antireflection and passivation of the back side.

[0037] Optionally, the first passivation layer 3 can be an aluminum oxide layer, and the thickness of the aluminum oxide layer can be 1.5 nm to 3 nm.

[0038] Optionally, the first antireflective film 2 is a silicon nitride layer, and the thickness of the silicon nitride layer is 60nm to 80nm.

[0039] Optionally, the thickness of the boron-doped polycrystalline silicon 4 is 300 nm to 800 nm.

[0040] In an optional embodiment, the TOPCon cell also includes a top electrode 1, which is located on the front side of the cell and is in contact with boron-doped polycrystalline silicon 4.

[0041] It is understood that in the embodiments of this application, "front" refers to the side facing the light and "back" refers to the side facing away from the light.

[0042] A second aspect of this application provides a photovoltaic module, the photovoltaic module comprising a half-cell, the half-cell being formed by laser non-destructive cleaving of the TOPCon cell described in the first aspect; the photovoltaic module is a half-cell module or a shingled module. Therefore, because the conversion efficiency of TOPCon cells after cleaving is higher than that of conventionally cleaved TOPCon cells, the power gain of the half-cell module or shingled module can be enhanced.

[0043] It's worth noting that half-cell modules involve cutting a complete solar cell in half, optimizing the series and parallel connection design to reduce resistance loss, and improving module power and hot spot resistance. Shingled modules, on the other hand, involve cutting the solar cell into 5-6 thin strips, interconnecting them with conductive adhesive layers to reduce grid line shading and improve module efficiency. Laser-based non-destructive cleaving can be used for this purpose.

[0044] The following section will conduct performance tests on the structure of the TOPCon battery provided in the embodiments of this application and related comparative examples.

[0045]

Example 1

[0046] 2. Double-sided flocking The front side of the silicon wafer is texturized with an alkaline solution (such as NaOH) to form an inverted pyramid textured surface structure with a reflectivity of less than 10%; the back side is polished to reduce defects.

[0047] 3. Preparation of front-side emitter Boron diffusion was performed at 850°C using a liquid BBr3 source to form p-type silicon wafers on the front side. + The emitter has a junction depth of approximately 1.2 μm.

[0048] 4. Fabrication of back-side passivated contact structure (401) Tunneling oxide layer deposition: A silicon oxide (SiO2) tunneling layer with a thickness of 1~2 nm is grown on the back side of the silicon wafer by thermal oxidation.

[0049] (402) Intrinsic polysilicon deposition and phosphorus doping: Using low-pressure chemical vapor deposition (LPCVD) technology, an intrinsic amorphous silicon (a-Si:H) layer is deposited on the tunneling oxide layer by thermal decomposition of silane (SiH4) at a pressure of approximately 133 Pa and a temperature of 600 °C.

[0050] Phosphorus diffusion treatment with phosphorus oxychloride (POCl3) at 850°C was used to crystallize the amorphous silicon layer into polycrystalline silicon (poly-Si), simultaneously forming n... + Doped polycrystalline silicon layer.

[0051] 5. Grooving and cleaning on the back (501) Laser grooving: In the predetermined cleaving area on the back side, a laser is used to groove (Note: the groove length extends through the cleaving area and the groove width is 200 μm) to remove the phosphosilicate glass (PSG), polysilicon and tunneling layer in the area, exposing the silicon substrate.

[0052] (502) Step cleaning: (a) Hydrofluoric acid (HF) cleaning: Removes PSG from the front side of the silicon wafer and PSG from the side surface.

[0053] (b) Alkali washing: Removes phosphorus-doped polysilicon that is coated around the sides and front of the silicon wafer.

[0054] (c) Secondary hydrofluoric acid (HF) cleaning: Remove PSG from the non-cracked area on the back side.

[0055] 6. Double-sided passivation and antireflection layer deposition (601) Atomic layer deposition (ALD): Alumina (Al2O3) films with a thickness of about 5 nm are deposited on the front and back sides of the silicon wafer.

[0056] (602) Plasma-enhanced chemical vapor deposition (PECVD): Depositing silicon nitride (SiN) layers with a thickness of approximately 80 nm on the front and back Al2O3 layers respectively. X Thin film, forming Al2O3 / SiN X Layered structure.

[0057] 7. Electrode preparation and activation (701) Screen printing: Silver (Ag) paste electrodes are printed on the front and back sides of the silicon wafer respectively.

[0058] (702) Sintering: High-temperature sintering of the printed battery.

[0059] (703) Photoinjection annealing: The battery is activated by photoinjection annealing to obtain a complete TOPCon battery.

[0060] 8. Front slotting Laser grooving (note: groove length 1mm, groove width 200 μm) is used at both ends of the front of the TOPCon battery (corresponding to the cracked area on the back) as the starting point for cracking.

[0061] 9. Laser-assisted non-destructive fracturing Using laser non-destructive cleaving technology (such as laser thermal stress cleaving), the cell is separated into two half-cells along the cleaving lines defined in step 5.1 (back side) and step 8 (front side).

[0062] Comparative Example 1 The other steps are the same as in the embodiment, except that there is no back-side slotting in step 5. Specifically: 1. Silicon wafer pretreatment A rectangular n-type single-crystal silicon wafer with dimensions of 210 mm × 182 mm (phosphorus-doped Czochralski method) is used, with a resistivity of 1~3 Ω·cm and a minority carrier lifetime greater than 1 ms.

[0063] 2. Double-sided flocking The front side of the silicon wafer is texturized with an alkaline solution (such as NaOH) to form an inverted pyramid textured surface structure with a reflectivity of less than 10%; the back side is polished to reduce defects.

[0064] 3. Preparation of front-side emitter Boron diffusion was performed at 850°C using a liquid BBr3 source to form p-type silicon wafers on the front side. + The emitter has a junction depth of approximately 1.2 μm.

[0065] 4. Fabrication of back-side passivated contact structure (401) Tunneling oxide layer deposition: A silicon oxide (SiO2) tunneling layer with a thickness of 1~2 nm is grown on the back side of the silicon wafer by thermal oxidation.

[0066] (402) Intrinsic polysilicon deposition and phosphorus doping: Using low-pressure chemical vapor deposition (LPCVD) technology, an intrinsic amorphous silicon (a-Si:H) layer is deposited on the tunneling oxide layer by thermal decomposition of silane (SiH4) at a pressure of approximately 133 Pa and a temperature of 600 °C.

[0067] Phosphorus diffusion treatment with phosphorus oxychloride (POCl3) at 850°C was used to crystallize the amorphous silicon layer into polycrystalline silicon (poly-Si), simultaneously forming n... + Doped polycrystalline silicon layer.

[0068] 5. Cleaning (a) Hydrofluoric acid (HF) cleaning: Removes PSG from the front side of the silicon wafer and PSG from the side surface.

[0069] (b) Alkali washing: Removes phosphorus-doped polysilicon that is coated around the sides and front of the silicon wafer.

[0070] (c) Secondary hydrofluoric acid (HF) cleaning: remove PSG from the back side.

[0071] 6. Double-sided passivation and antireflection layer deposition (601) Atomic layer deposition (ALD): Alumina (Al2O3) films with a thickness of about 5 nm are deposited on the front and back sides of the silicon wafer.

[0072] (602) Plasma-enhanced chemical vapor deposition (PECVD): Depositing silicon nitride (SiN) layers with a thickness of approximately 80 nm on the front and back Al2O3 layers respectively. X Thin film, forming Al2O3 / SiN X Layered structure.

[0073] 7. Electrode preparation and activation (701) Screen printing: Silver (Ag) paste electrodes are printed on the front and back sides of the silicon wafer respectively.

[0074] (702) Sintering: High-temperature sintering of the printed battery.

[0075] (703) Photoinjection annealing: The battery is activated by photoinjection annealing to obtain a complete TOPCon battery.

[0076] 8. Front slotting Laser grooving (note: groove length 1mm, groove width 200 μm) is used at both ends of the front of the TOPCon battery (corresponding to the cracked area on the back) as the starting point for cracking.

[0077] 9. Laser-assisted non-destructive fracturing Using laser non-destructive cleaving technology (such as laser thermal stress cleaving), the cleaving line defined in step 8 (front side) separates the cell into two half-cells.

[0078] The half-cell batteries of Example 1 and Comparative Example 1 were subjected to IV tests, and the specific data are shown in Table 1.

[0079] Table 1:

[0080] As can be seen from Table 1 above, the half-cell cell of Example 1 is superior to that of Comparative Example 1. This is because the TOPCon cell of Example 1 does not have a tunneling layer and a polycrystalline silicon layer in the cleavage area on the back, which can effectively eliminate cleavage damage and thus enable the cleavage to maintain a high efficiency.

[0081] This application embodiment can also provide a photovoltaic module (not shown), which includes a half-cell obtained by laser non-destructive cleaving of the TOPCon cell as described above. The half-cell can be connected in series and / or in parallel with one or more other solar cells in a predetermined manner. Multiple cells can form a cell string, and adjacent cells can be connected together by string welding.

[0082] It should be noted that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential," etc., are used only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this application. The directional terms "inner" and "outer" refer to the inside or outside relative to the outline of the component itself. For example, if a device in the drawings is inverted, a device described as "above" or "on top of other devices or structures" will subsequently be positioned as "below" or "under" other devices or structures. Thus, the exemplary term "above" can include both "above" and "below." The device may also be positioned in other different ways (rotated 90 degrees or in other orientations), and the spatial relative descriptions used herein are interpreted accordingly.

[0083] It should also be noted that the terms "one embodiment," "another embodiment," and "embodiment" used in this application refer to specific features, structures, or characteristics described in connection with that embodiment, which are included in at least one embodiment described in the general description of this application. The appearance of the same expression in multiple places in the specification does not necessarily refer to the same embodiment. Furthermore, when a specific feature, structure, or characteristic is described in connection with any embodiment, the intention is to suggest that implementing such a feature, structure, or characteristic in conjunction with other embodiments also falls within the scope of this application.

[0084] In the above embodiments, the descriptions of each embodiment have different focuses. For parts not described in detail in a certain embodiment, please refer to the relevant descriptions in other embodiments.

[0085] It should also be noted that the above are merely preferred embodiments of this application and do not limit the scope of patent protection of this application. Any equivalent structural or procedural changes made using the content of this application’s specification and drawings, or direct or indirect applications in other related technical fields, are similarly included within the scope of patent protection of this application.

Claims

1. A TOPCon battery, characterized in that, The TOPCon battery has a front and a back side arranged opposite to each other, and the back side includes a continuously arranged cleaved area and a non-cleaved area. The non-cracked region is provided with a passivated contact structure, while the cracked region is not provided with a passivated contact structure.

2. The TOPCon cell according to claim 1, characterized in that The cleavage region has a first cutting edge and a second cutting edge arranged opposite to each other, and the distance between the first cutting edge and the second cutting edge is 40μm to 500μm.

3. The TOPCon cell according to claim 1, characterized in that, The cross-section of the cleavage region is rectangular.

4. The TOPCon cell of claim 1, wherein, The passivated contact structure includes a stacked tunneling layer and doped polysilicon.

5. The TOPCon cell according to claim 1, characterized in that, The TOPCon battery includes: N-type silicon substrate (5), the N-type silicon substrate (5) having a front side and a back side disposed opposite to each other, the back side including a continuously disposed cleaved region and a non-cleaved region; A tunneling layer (6) is stacked on the non-cracked region of the N-type silicon substrate (5); Phosphorus-doped polycrystalline silicon (7) is stacked on the side of the tunneling layer (6) away from the N-type silicon substrate (5).

6. The TOPCon cell according to claim 5, characterized in that, The TOPCon battery also includes: The second passivation layer (8) is stacked on the side of the phosphorus-doped polysilicon (7) away from the tunneling layer (6) and on the cleavage region of the N-type silicon substrate (5). The second antireflective film (9) is stacked on the side of the second passivation layer (8) away from the N-type silicon substrate (5).

7. The TOPCon cell according to claim 6, characterized in that The TOPCon battery satisfies at least one of the following characteristics: (1) The tunneling layer (6) is a SiO2 layer, and the thickness of the tunneling layer (6) is 1 nm to 2 nm; (2) The thickness of the phosphorus-doped polycrystalline silicon (7) is 80 nm to 200 nm; (3) The second passivation layer (8) is an aluminum oxide layer, and the thickness of the aluminum oxide layer is 1.5 nm to 3 nm; (4) The second antireflective film (9) is a silicon nitride layer, and the thickness of the silicon nitride layer is 60nm to 80nm; (5) The TOPCon battery also includes a back electrode (10), one end of which is in contact with the phosphorus-doped polycrystalline silicon (7).

8. The TOPCon cell according to claim 5, characterized in that, The front side of the N-type silicon substrate (5) is sequentially stacked with boron-doped polycrystalline silicon (4), a first passivation layer (3) and a first antireflection film (2) in the first direction. The first direction is from the N-type silicon substrate (5) to the direction away from the N-type silicon substrate (5).

9. The TOPCon cell according to claim 8, characterized in that, The first passivation layer (3) is an aluminum oxide layer, and the thickness of the aluminum oxide layer is 1.5 nm to 3 nm; and / or The first antireflective coating (2) is a silicon nitride layer, the thickness of which is 60 nm to 80 nm; and / or The thickness of the boron-doped polycrystalline silicon (4) is 300 nm to 800 nm.

10. A photovoltaic module, characterized by, The photovoltaic module includes a half-cell, which is formed by laser non-destructive splitting of the TOPCon cell according to any one of claims 1 to 9; The photovoltaic module is a half-cell module or a shingled module.

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