Solar cell
By layering a field passivation layer and a hydrogen passivation layer on the cut surface of the solar cell, the problem of dangling bonds affecting efficiency on the cut surface is solved, achieving stronger passivation protection and improved efficiency.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-01-22
- Publication Date
- 2026-03-27
AI Technical Summary
The cut surface in solar cells contains dangling bonds, which affects the cell's conversion efficiency and requires stronger passivation protection.
A field passivation layer and a hydrogen passivation layer are layered on the cut surface. The field passivation layer repels minority carriers through an electric field, while the hydrogen passivation layer reduces the recombination of defect states with photogenerated carriers by combining hydrogen atoms with dangling bonds.
This improves the passivation protection of the cut surface and enhances the conversion efficiency of solar cells.
Smart Images
Figure CN224054710U_ABST
Abstract
Description
[0001] The present application claims priority to the Chinese patent application No. 202422951804.1, filed on November 29, 2024, and entitled "A solar cell", the content of which is incorporated herein by reference in its entirety. TECHNICAL FIELD
[0002] The utility model relates to photovoltaic technology field, especially relate to a solar cell. BACKGROUND
[0003] The ASP technology (Advanced Surface Passivation Technology) first cuts the whole cell piece by laser, thereby forming a cutting surface on the side surface of the cell piece, and then a passivation film is used to passivate the cutting surface. Since it has good effect on repairing micro-damage and can reduce passivation loss, it can improve the conversion efficiency of the cell and the module, and the power of the TOPCon (Tunnel Oxide Passivating Contact) 72 double-glass module can be increased by 4W+. However, since there are a large number of dangling bonds on the cutting surface, it will affect the conversion efficiency of the cell, so the cutting surface needs strong passivation protection. SUMMARY
[0004] Therefore, the utility model aims to provide a solar cell for improving the passivation protection of the cutting surface.
[0005] To solve the above technical problems, the utility model provides a solar cell, comprising: a cell piece; at least one side surface of the cell piece forms a cutting surface; the cutting surface is arranged with at least one layer of first passivation layer and at least one layer of second passivation layer; the first passivation layer is a field passivation layer; and the second passivation layer is a hydrogen passivation layer.
[0006] Optionally, the fixed charge density of the first passivation layer is greater than that of the second passivation layer.
[0007] Optionally, the fixed charge density of the first passivation layer is 2x10 12 cm -2 ~13x10 12 cm -2 , and includes the values at both ends.
[0008] The fixed charge density of the second passivation layer is 1x10 11 cm -2 ~15x10 11 cm -2 , and includes the values at both ends.
[0009] Optionally, the total thickness of all the first passivation layers and all the second passivation layers is 30-100 nm, inclusive.
[0010] Optionally, the thickness of the first passivation layer is 5-60 nm, inclusive.
[0011] Optionally, the thickness of the second passivation layer is 5-60 nm, inclusive.
[0012] Optionally, the cut surface is sequentially stacked with a layer of the first passivation layer and a layer of the second passivation layer.
[0013] Optionally, the cut surface is sequentially stacked with a layer of the second passivation layer and a layer of the first passivation layer.
[0014] Optionally, the cut surface is sequentially stacked with a layer of the first passivation layer and a layer of the second passivation layer.
[0015] Optionally, the first passivation layer is a hydrogen-poor AlO layer, a hydrogen-poor SIN layer, or a hydrogen-poor SiO layer. x x x
[0016] Optionally, the second passivation layer is a hydrogen-rich AlO layer, a hydrogen-rich SIN layer, a hydrogen-rich SiO layer, a hydrogen-rich SiON layer, a hydrogen-rich AlN layer, or a hydrogen-rich AlON layer. x x x x x
[0017] Optionally, the content of hydrogen atoms in the second passivation layer is 1.5-4.5 at.%, inclusive.
[0018] Optionally, the cell includes a substrate; the front surface of the substrate is sequentially provided with a diffusion layer, a front passivation layer, an anti-reflection layer, and a front electrode along the thickness direction of the substrate; the back surface of the substrate is sequentially provided with a tunneling layer, a doped polysilicon layer, a back passivation layer, and a back electrode along the thickness direction of the substrate.
[0019] The utility model provides a solar cell, including: cell piece, the cell piece at least one side lateral surface forms cutting surface, cutting surface has at least one layer first passivation layer and at least one layer second passivation layer in the layered arrangement, first passivation layer is field passivation layer, second passivation layer is hydrogen passivation layer. The utility model discloses a cutting surface is layered along the thickness direction and is provided with two different effect passivation layers of field passivation and hydrogen passivation can be formed, thereby improves the passivation protection effect to cutting surface. BRIEF DESCRIPTION OF DRAWINGS
[0020] In order to more clearly illustrate the technical scheme in the embodiments of the utility model or prior art, the following will briefly introduce the drawings needed to be used in the embodiment or prior art description, obviously, the drawings in the following description only are the embodiment of the utility model, and for the ordinary skilled person in the art, under the premise of not paying the creative labor, still can obtain other drawings according to the provided drawings.
[0021] Figure 1 The utility model provides a solar cell's structural schematic diagram.
[0022] The reference signs are explained as follows:
[0023] 1-cell piece;11-substrate;12-diffusion layer;13-front passivation layer;14-anti-reflection layer;15-front electrode;16-tunneling layer;17-doped polysilicon layer;18-back passivation layer;19-back electrode;21-first passivation layer;22-second passivation layer. DETAILED DESCRIPTION
[0024] In order to make the purpose, technical scheme and advantage of the embodiment of the utility model more clear, the following will combine the drawings in the embodiment of the utility model, and the technical scheme in the embodiment of the utility model is clearly and completely described, obviously, the described embodiment only is a part of the embodiment of the utility model, not all the embodiment. Based on the embodiment in the utility model, all other embodiments obtained by the ordinary skilled person in the art without making the creative labor belong to the range of protection of the utility model.
[0025] Please refer to Figure 1 , Figure 1 The utility model provides a solar cell's structural schematic diagram. The solar cell can include: cell piece 1;Cell piece 1 at least one side lateral surface forms cutting surface;Cutting surface has at least one layer first passivation layer 21 and at least one layer second passivation layer 22 in the layered arrangement;First passivation layer 21 is field passivation layer;Second passivation layer 22 is hydrogen passivation layer.
[0026] It should be noted that the field passivation layer is a passivation layer capable of forming field passivation on the cutting surface, and the principle of field passivation is to generate an electric field on the surface, repel minority carriers, and make the minority carriers away from the surface or defect region, thereby reducing the recombination of carriers on the surface; the hydrogen passivation layer is a passivation layer capable of forming hydrogen passivation on the cutting surface, and the principle of hydrogen passivation is to combine hydrogen atoms with defect states such as dangling bonds to reduce the recombination effect of defect states on photo-generated carriers.
[0027] The embodiment does not limit the specific number of the first passivation layer 21 and the second passivation layer 22, for example, the cutting surface can be arranged in layers with one layer of the first passivation layer 21 and one layer of the second passivation layer 22; or the cutting surface is provided with a plurality of layers of the first passivation layer 21 and a plurality of layers of the second passivation layer 22 arranged in layers along the thickness direction; the first passivation layer 21 and the second passivation layer 22 are alternately arranged in layers. It should be noted that any one of the above arrangement methods can improve the passivation protection effect on the cutting surface in the embodiment.
[0028] The embodiment does not limit the specific arrangement order of the first passivation layer 21 and the second passivation layer 22, for example, when the cutting surface is arranged in layers with one layer of the first passivation layer 21 and one layer of the second passivation layer 22, the cutting surface can be sequentially stacked with one layer of the first passivation layer 21 and one layer of the second passivation layer 22; or, the cutting surface can be sequentially stacked with one layer of the second passivation layer 22 and one layer of the first passivation layer 21; when the cutting surface is arranged in layers with a plurality of layers of the first passivation layer 21 and a plurality of layers of the second passivation layer 22, the cutting surface can be sequentially and alternately stacked with a plurality of layers of the first passivation layer 21 and a plurality of layers of the second passivation layer 22, that is, the cutting surface can be sequentially stacked with one layer of the first passivation layer 21, one layer of the second passivation layer 22, one layer of the first passivation layer 21 and one layer of the second passivation layer 22, and so on; or, the cutting surface can be sequentially and alternately stacked with a plurality of layers of the second passivation layer 22 and a plurality of layers of the first passivation layer 21, that is, the cutting surface can be sequentially stacked with one layer of the second passivation layer 22, one layer of the first passivation layer 21, one layer of the second passivation layer 22 and one layer of the first passivation layer 21, and so on.
[0029] The embodiment does not limit the specific thickness of the first passivation layer 21, and the specific thickness of the first passivation layer 21 affects the passivation effect of the first passivation layer 21, for example, the thickness of the first passivation layer 21 can be 5nm-60nm, and the values at both ends are included. In order to achieve the best field passivation effect, the preferred thickness of the first passivation layer 21 in the embodiment can be 5nm, 6nm, 7nm, 8nm, 9nm…58nm, 59nm or 60nm.
[0030] The embodiment does not limit the specific thickness of the second passivation layer 22, and the specific thickness of the second passivation layer 22 affects the passivation effect of the second passivation layer 22. For example, the thickness of the second passivation layer 22 can be 5 nm to 60 nm, and the values at both ends are included. In order to achieve the best hydrogen passivation effect, the preferred thickness of the second passivation layer 22 in the embodiment can be 5 nm, 6 nm, 7 nm, 8 nm, 9 nm, 58 nm, 59 nm or 60 nm.
[0031] The embodiment does not limit the specific total thickness of all the first passivation layers 21 and all the second passivation layers 22, and the specific total thickness of all the first passivation layers 21 and all the second passivation layers 22 affects the overall passivation effect of the stacked passivation layer. For example, the total thickness of all the first passivation layers 21 and all the second passivation layers 22 can be 30 nm to 100 nm, and the values at both ends are included. In order to achieve the best passivation effect, the preferred total thickness of all the first passivation layers 21 and all the second passivation layers 22 in the embodiment can be 31 nm, 32 nm, 33 nm, 34 nm, 35 nm, 98 nm, 99 nm or 100 nm.
[0032] The embodiment does not limit the specific type of the first passivation layer 21, as long as it can form a field passivation layer on the cutting surface. For example, the first passivation layer 21 can be a hydrogen-poor AlO x layer, a hydrogen-poor SIN x layer or a hydrogen-poor SiO x layer. It should be noted that the hydrogen-poor AlO x layer, the hydrogen-poor SIN x layer or the hydrogen-poor SiO x layer is a common material obtained by the PECVD (Plasma Enhanced Chemical Vapor Deposition) method in the prior art. The embodiment does not limit the internal components of the first passivation layer 21, but directly uses the film layer made of the existing material as the first passivation layer 21.
[0033] It should be noted that there can be a mixed layer between the first passivation layer 21 and the second passivation layer 22 in the embodiment. The mixed layer is formed because part of the hydrogen in the hydrogen passivation layer (i.e., the second passivation layer 22) enters the field passivation layer (i.e., the first passivation layer 21) during the preparation process. This phenomenon is caused by process reasons, and the mixed layer formed belongs to a reasonable level. In the embodiment, hydrogen-poor means not containing or containing a small amount of hydrogen atoms. The reason for containing a small amount of hydrogen atoms is that a small amount of hydrogen atoms in the hydrogen passivation layer enter the field passivation layer during the preparation process; hydrogen-rich means containing hydrogen atoms.
[0034] In addition, it should be noted that the AlO xSiO x The high density has a strong field passivation protection effect, and the hydrogen-poor AlO x layer is arranged on the side close to the cutting surface, and the hydrogen-rich AlO x layer is arranged on the side away from the cutting surface of the hydrogen-poor AlO x layer, in addition to the field passivation effect of the first passivation layer 21, the hydrogen chemical passivation of the second passivation layer 22 further enhances the passivation ability. When the first passivation layer 21 is a hydrogen-poor SiO x layer, the hydrogen-rich SiO x layer is arranged on the side close to the cutting surface, and the hydrogen-poor SiO x layer is arranged on the side away from the cutting surface of the hydrogen-rich SiO x layer.
[0035] It should be noted that the fixed charge density affects the field passivation effect, in order to improve the field passivation effect, the fixed charge density of the first passivation layer 21 in the embodiment can be greater than the fixed charge density of the second passivation layer 22.
[0036] The embodiment does not limit the specific fixed charge density of the first passivation layer 21, for example, the fixed charge density of the first passivation layer 21 can be 2×10 12 cm -2 ~13×10 12 cm -2 , and includes both ends. In order to achieve the best field passivation effect, the fixed charge density of the first passivation layer 21 in the embodiment is preferably 2×10 12 cm -2 , 3×10 12 cm -2 , 4×10 12 cm -2 , 5×10 12 cm -2 , 6×10 12 cm -2 , 7×10 12 cm -2 , 8×10 12 cm -2 , 9×10 12 cm -2 , 10×10 12 cm -2 , 11×10 12 cm -2 , 12×10 12 cm -2 or 13×10 12 cm -2 . It should be noted that the fixed charge density is 2×10 12 cm-2 13 x 1011 12 cm -2 (both ends inclusive) is a common material grown by the PECVD method and obtained by adjusting process parameters in the prior art. The present embodiment is not limited to the internal composition of the first passivation layer 21, but directly uses a film layer made of the existing material as the first passivation layer 21 with a fixed charge density of 13 x 1011 12 cm -2 13 x 1011 12 cm -2 (both ends inclusive) as the first passivation layer 21.
[0037] The present embodiment is not limited to the specific type of the second passivation layer 22, as long as it can form hydrogen passivation on the cut surface. For example, the second passivation layer 22 can be a hydrogen-rich AlO x layer, a hydrogen-rich SIN x layer, a hydrogen-rich SiO x layer, a hydrogen-rich SiON x layer, a hydrogen-rich AlN x layer, or a hydrogen-rich AlON layer. It should be noted that the hydrogen-rich AlO x layer, the hydrogen-rich SIN x layer, the hydrogen-rich SiO x layer, the hydrogen-rich SiON x layer, the hydrogen-rich AlN x layer, or the hydrogen-rich AlON layer are all common materials grown by the ALD (Atomic Layer Deposition) method in the prior art, in which the hydrogen-rich AlO x layer is grown using TMA (Trimethylaluminum Alumina) and oxygen. The present embodiment is not limited to the internal composition of the second passivation layer 22, but directly uses a film layer made of the existing material as the second passivation layer 22.
[0038] The embodiment does not limit the specific content of hydrogen atoms in the second passivation layer 22. The specific content of hydrogen atoms in the second passivation layer 22 affects the passivation effect of the second passivation layer 22. For example, the content of hydrogen atoms in the second passivation layer 22 can be 1.5 at.% to 4.5 at.%, and the values at both ends are included. In order to achieve the best hydrogen passivation effect, the preferred content of hydrogen atoms in the second passivation layer 22 in the embodiment can be 1.5 at.%, 1.6 at.%, 1.7 at.%, 1.8 at.%, 1.9 at.%... 4.3 at.%, 4.4 at.% or 4.5 at.%. It should be noted that the passivation layer with a content of hydrogen atoms of 1.5 at.% to 4.5 at.% (and the values at both ends are included) is a common material grown by the ALD method and obtained by adjusting the process parameters in the prior art. The embodiment does not limit the internal components of the second passivation layer 22, but directly uses the passivation layer with a content of hydrogen atoms of 1.5 at.% to 4.5 at.% (and the values at both ends are included) as the second passivation layer 22, which is a film layer made of the existing material.
[0039] The embodiment does not limit the specific fixed charge density of the second passivation layer 22. For example, the fixed charge density of the second passivation layer 22 can be 1×10 11 cm -2 ~15×10 11 cm -2 , and the values at both ends are included. It should be noted that the passivation layer with a fixed charge density of 1×10 11 cm -2 ~15×10 11 cm -2 (at both ends) is a common material grown by the ALD method and obtained by adjusting the process parameters in the prior art. The embodiment does not limit the internal components of the second passivation layer 22, but directly uses the passivation layer with a fixed charge density of 1×10 11 cm -2 ~15×10 11 cm -2 (at both ends) as the second passivation layer 22, which is a film layer made of the existing material.
[0040] The embodiment does not limit the specific number of cutting surfaces. The specific number of cutting surfaces can be determined according to the actual cutting method. For example, when the battery piece 1 is obtained by one cutting, the cutting surface can be formed on one side surface of the battery piece 1. When the battery piece 1 is obtained by twice cutting, the cutting surfaces can be respectively formed on the opposite side surfaces of the battery piece 1.
[0041] The embodiment is not limited to the specific type of the battery piece 1. For example, the battery piece 1 can be a TOPCon battery piece, which specifically can include a substrate 11; the front surface of the substrate 11 is sequentially provided with a diffusion layer 12, a front surface passivation layer 13, an anti-reflection layer 14 and a front surface electrode 15 along the thickness direction of the substrate 11 itself; the back surface of the substrate 11 is sequentially provided with a tunneling layer 16, a doped polysilicon layer 17, a back surface passivation layer 18 and a back surface electrode 19 along the thickness direction of the substrate 11 itself.
[0042] The embodiment is not limited to the specific type of the substrate 11. The substrate 11 can be, but is not limited to, an N-type substrate or a P-type substrate. The embodiment is not limited to the specific type of the substrate 11. The substrate 11 can be, but is not limited to, a silicon substrate. It should be noted that silicon is a common material in the prior art. The embodiment is not limited to the internal components of the substrate 11, but directly uses a silicon substrate made of existing materials. The embodiment is not limited to the specific thickness of the substrate 11. The thickness of the substrate 11 can be 100 μm to 200 μm, and the values at both ends are included.
[0043] Further, in order to improve the light trapping effect of the front surface of the substrate 11, the front surface of the substrate 11 can have a pyramid texture in the embodiment.
[0044] The embodiment is not limited to the specific type of the diffusion layer 12. The specific type of the diffusion layer 12 can be determined according to the specific type of the substrate 11. For example, when the substrate 11 is an N-type substrate, the diffusion layer 12 can be a P-type diffusion layer; when the substrate 11 is a P-type substrate, the diffusion layer 12 can be an N-type diffusion layer. Among them, the P-type diffusion layer is doped with P-type impurities, and the N-type diffusion layer is doped with N-type impurities.
[0045] The embodiment is not limited to the specific type of the front surface passivation layer 13. The front surface passivation layer 13 can include, but is not limited to, an AlO x layer. It should be noted that AlO x layer is a common material in the prior art. The embodiment is not limited to the internal components of the front surface passivation layer 13, but directly uses a film layer made of existing materials as the front surface passivation layer 13. The embodiment is not limited to the specific thickness of the front surface passivation layer 13. The thickness of the front surface passivation layer 13 can be 4 nm to 8 nm, and the values at both ends are included. In order to achieve the best passivation effect, the preferred thickness of the front surface passivation layer 13 in the embodiment can be 4 nm, 5 nm, 6 nm, 7 nm or 8 nm.
[0046] The embodiment is not limited to the specific type of the anti-reflective layer 14, and the anti-reflective layer 14 can include, but is not limited to, a silicon nitride layer. It should be noted that the silicon nitride layer is a common material in the prior art, and the embodiment is not limited to the internal components of the anti-reflective layer 14, but directly uses a film layer made of the existing material as the anti-reflective layer 14. The embodiment is not limited to the specific thickness of the anti-reflective layer 14, and the thickness of the anti-reflective layer 14 can be 70 nm to 90 nm, and the values at both ends are included. In order to achieve the best anti-reflective effect, it should be noted that the preferred thickness of the anti-reflective layer 14 in the embodiment can be 70 nm, 71 nm, 72 nm, 73 nm, 74 nm, …, 88 nm, 89 nm, or 90 nm.
[0047] The embodiment is not limited to the specific type of the front electrode 15, and the front electrode 15 can include, but is not limited to, a silver emitter or an aluminum emitter. It should be noted that silver and aluminum are common materials in the prior art, and the embodiment is not limited to the internal components of the front electrode 15, but directly uses an emitter made of the existing material as the front electrode 15.
[0048] The embodiment is not limited to the specific type of the tunnel layer 16, and the tunnel layer 16 can include, but is not limited to, a silicon oxide layer. It should be noted that the silicon oxide layer is a common material in the prior art, and the embodiment is not limited to the internal components of the tunnel layer 16, but directly uses a film layer made of the existing material as the tunnel layer 16. The embodiment is not limited to the specific thickness of the tunnel layer 16, and the thickness of the tunnel layer 16 can be 1.2 nm to 2 nm, and the values at both ends are included. It should be noted that the thickness of the tunnel layer 16 will affect the performance of the solar cell, and in order to achieve the best performance, the preferred thickness of the tunnel layer 16 in the embodiment can be 1.2 nm, 1.3 nm, 1.4 nm, 1.5 nm, 1.6 nm, 1.7 nm, 1.8 nm, 1.9 nm, or 2 nm.
[0049] The embodiment is not limited to the specific type of the doped polysilicon layer 17, and the specific type of the doped polysilicon layer 17 can be determined according to the specific type of the substrate 11, for example, when the substrate 11 is an N-type substrate, the doped polysilicon layer 17 can be an N-type doped polysilicon layer; when the substrate 11 is a P-type substrate, the doped polysilicon layer 17 can be a P-type doped polysilicon layer. The N-type doped polysilicon layer is doped with N-type impurities, and the P-type doped polysilicon layer is doped with P-type impurities. The embodiment is not limited to the specific thickness of the doped polysilicon layer 17, and the thickness of the doped polysilicon layer 17 can be 90-200 nm, and the values at both ends are included. It should be noted that the thickness of the doped polysilicon layer 17 will affect the performance of the solar cell, and in order to achieve the best performance, the preferred thickness of the doped polysilicon layer 17 in the embodiment can be 90 nm, 91 nm, 92 nm, 93 nm, 94 nm, 198 nm, 199 nm or 200 nm.
[0050] The embodiment is not limited to the specific type of the back passivation layer 18, and the back passivation layer 18 can include but is not limited to a silicon nitride layer. It should be noted that the silicon nitride layer is a common material in the prior art, and the embodiment is not limited to the internal components of the back passivation layer 18, but directly uses a film layer made of an existing material as the back passivation layer 18. The embodiment is not limited to the specific thickness of the back passivation layer 18, and the thickness of the back passivation layer 18 can be 70-90 nm, and the values at both ends are included. In order to achieve the best antireflection effect, it should be noted that the preferred thickness of the back passivation layer 18 in the embodiment can be 70 nm, 71 nm, 72 nm, 73 nm, 74 nm, 88 nm, 89 nm or 90 nm.
[0051] The embodiment is not limited to the specific type of the back passivation layer 18, and the back passivation layer 18 can include but is not limited to a silicon nitride layer. It should be noted that the silicon nitride layer is a common material in the prior art, and the embodiment is not limited to the internal components of the back passivation layer 18, but directly uses a film layer made of an existing material as the back passivation layer 18. The embodiment is not limited to the specific thickness of the back passivation layer 18, and the thickness of the back passivation layer 18 can be 70-90 nm, and the values at both ends are included. In order to achieve the best antireflection effect, it should be noted that the preferred thickness of the back passivation layer 18 in the embodiment can be 70 nm, 71 nm, 72 nm, 73 nm, 74 nm, 88 nm, 89 nm or 90 nm.
[0052] Based on the above embodiment, the utility model discloses a kind of passivation layers of different effects of being able to form field passivation and being able to form hydrogen passivation by being layered along the thickness direction in cutting surface, to improve the passivation protection effect to cutting surface.
[0053] The above has carried out detailed introduction to the solar cell provided by the utility model, for the general technical personnel of the field, according to the thought of the embodiment of the utility model, there will be changes in specific implementation and application range, and the above is described, the content of the specification should not be understood as the limitation of the utility model.
Claims
1. A solar cell, characterized by, Comprise: a battery piece; a cutting surface is formed on at least one side surface of the battery piece; the cutting surface is arranged in layers with at least one first passivation layer and at least one second passivation layer; the first passivation layer is a field passivation layer; the second passivation layer is a hydrogen passivation layer; said first passivation layer is a hydrogen-poor AlO x layer; said second passivation layer is a hydrogen-rich AlO x layer; said hydrogen-poor AlO x layer is arranged on the side facing the cutting face, said hydrogen-rich AlO x layer is arranged on the side of the hydrogen-poor AlO x layer facing away from the cutting face The fixed charge density of the first passivation layer is greater than that of the second passivation layer.
2. The solar cell according to claim 1, characterized in that, The total thickness of all the first passivation layers and all the second passivation layers is 30-100 nm, including both ends.
3. The solar cell according to claim 1, characterized in that, The thickness of the first passivation layer is 5-60 nm, including both ends. And / or, the thickness of the second passivation layer is 5-60 nm, including both ends.
4. The solar cell of claim 1, wherein The cutting surface is sequentially stacked with one first passivation layer and one second passivation layer; Or, the cutting surface is sequentially stacked with one second passivation layer and one first passivation layer.
5. The solar cell of claim 1, wherein The cutting surface is arranged in layers with a plurality of first passivation layers and a plurality of second passivation layers; the first passivation layers and the second passivation layers are alternately arranged in layers.
6. The solar cell according to any one of claims 1 to 5, wherein The battery piece includes a substrate; the front surface of the substrate is sequentially provided with a diffusion layer, a front passivation layer, an anti-reflection layer and a front electrode along its own thickness direction; the back surface of the substrate is sequentially provided with a tunneling layer, a doped polysilicon layer, a back passivation layer and a back electrode along its own thickness direction.