59results about How to "Improve battery efficiency" patented technology

The invention belongs to the technical field of back contact cells, and particularly relates to a joint passivation back contact cell and a post-texturing preparation method thereof, and the method comprises the steps: S102, sequentially forming a first semiconductor layer and a mask layer on the back surface of a silicon substrate; s103, cleaning and texturing are carried out, so that a texturing surface is formed on the light receiving surface of the silicon substrate, and the maximum height of a pyramid of the texturing surface of the light receiving surface is T1; s104, sequentially forming a passivation layer and an anti-reflection layer on the light receiving surface of the silicon substrate; s105, forming a second semiconductor opening region; s106, cleaning and etching are carried out, and a groove structure is at least formed in the second semiconductor opening region on the back surface of the silicon substrate; and S107, depositing a second semiconductor layer on the back surface, wherein the second semiconductor layer comprises an amorphous passivation layer and a second doped silicon layer. Under the conditions of simplifying the process steps and reducing the material cost, the interface contact resistance of the second semiconductor opening region can be reduced, the minority carrier lifetime is prolonged, and the cell efficiency and the double-sided rate are improved.

The invention relates to the technical field of perovskite solar cell preparation, in particular to a bulk phase passivation perovskite light absorption layer, a solar cell and a preparation method, the bulk phase passivation perovskite light absorption layer is prepared by adopting a perovskite layer prefabricated liquid, the perovskite layer prefabricated liquid comprises (FA 0.95 MA0.05) 0.95 Cs0.05 Pb (I 0.95 Br0.05) 3 and m-F-PEACl, the molar concentration ratio of the (FA 0.95 MA0.05) 0.95 Cs0.05 Pb (I 0.95 Br0.05) 3 to the m-F-PEACl is 1.5: (0.1-1), m-F-PEACl and (FA < 0.95 > MA0. 05) < 0.95 > Cs0. 05Pb (I < 0.95 > Br0. 05) 3 are matched to form a bulk phase passivated perovskite layer, so that organic cations in the m-F-PEACl interact with uncoordinated lead ions or other defect sites in the (FA < 0.95 > MA0. 05) < 0.95 > Cs0. 05Pb (I < 0.95 > Br0. 05) 3 to form a stable complex or compound, the defect concentration in perovskite is reduced, comprehensive and effective passivation is realized, and the performance of the perovskite is improved. Therefore, the photoelectric property and the stability of the perovskite material are improved. The problem that comprehensive and effective passivation cannot be achieved through a perovskite thin film passivation method in the prior art is solved.

The invention provides a hybrid passivation back contact battery and a preparation method thereof. The battery comprises a silicon wafer; a third tunneling oxide layer, a first amorphous silicon layer and a first anti-reflection layer are sequentially arranged on the front surface of the silicon wafer; first polishing areas and second polishing areas are alternately arranged on the back surface of the silicon wafer; a first semiconductor layer is at least arranged on the first polishing area; a second semiconductor layer is at least arranged on the second polishing area; a texturing area is arranged between the first polishing area and the adjacent second polishing area; a fourth tunneling oxide layer, a second amorphous silicon layer and a second antireflection layer are sequentially arranged on each of the first polishing region, the texturing region and the second polishing region; the refractive index of the first amorphous silicon layer is 2.2-4, and the refractive index of the first amorphous silicon layer is gradually reduced in the direction from the third tunneling oxide layer to the first anti-reflection layer. According to the invention, the passivation effect is improved, so that the battery efficiency is improved. In addition, the passivation layers on the front surface and the back surface can be deposited and formed in the same tubular PECVD, so that the process steps are simplified, and the equipment cost is reduced.

The invention discloses a TOPCon electroplated cell and an edge passivation method for reducing cutting damage of the TOPCon electroplated cell, and relates to the technical field of solar cells. The method comprises the following steps: growing a layer of aluminum oxide film on the surfaces and edges of a plurality of small battery pieces formed by laser slicing, and then sintering, annealing and carrying out light injection to obtain passivated small battery pieces; and coating the edge of the passivated small battery piece with a layer of UV glue, and then carrying out ultraviolet radiation, acid pickling, water washing and drying to obtain the edge-passivated small battery piece. Edge passivation is completed before nickel, copper and tin are electroplated to manufacture the grid line, the effect of repairing cutting damage is achieved, a high-temperature process is not needed subsequently, the adhesive force of the electroplated grid line can be guaranteed, and the efficiency of the cut battery is improved.

The invention provides an IBC solar cell. The IBC solar cell comprises a silicon substrate; the tunneling oxide layer comprises a first tunneling oxide layer formed on the front surface of the silicon substrate and a second tunneling oxide layer formed on the back surface of the silicon substrate; the doped silicon-containing film layer is arranged on one side, opposite to the silicon substrate, of the second tunneling oxide layer; wherein the number of defects in the first tunneling oxide layer tends to zero or is zero, the second tunneling oxide layer comprises defects, the defects are pits and / or pinholes, and the pinholes penetrate through the tunneling oxide layer. The battery efficiency of the IBC solar battery provided by the embodiment of the invention is further improved.

The invention discloses a solid hydrogen storage fuel cell system capable of measuring the residual hydrogen amount and a hydrogen energy two-wheeled vehicle. The solid hydrogen storage fuel cell system comprises an electric pile, a hydrogen supply module, an air supply module, a hydrogen desorption heating module and a cell management control module. According to the solid-state hydrogen storage fuel cell system provided by the invention, the temperature of inlet air can be controlled, and the humidity of supplied air can be regulated and controlled, so that higher cell efficiency can be obtained; the residual hydrogen amount can be estimated by combining the hydrogen supply control unit for air inlet temperature control and the hydrogen residual amount estimation sub-module through a specific algorithm, then the hydrogen desorption temperature is optimized according to the estimation result of the residual hydrogen amount, the hydrogen desorption temperature is properly increased, the decrease of the hydrogen desorption rate caused by the decrease of the residual hydrogen amount can be made up, and the hydrogen desorption efficiency is improved. And the hydrogen desorption rate can be maintained near a set value, so that the supply of hydrogen is better ensured.

The invention provides a solar cell and a manufacturing method of the solar cell, and mainly relates to the technical field of photovoltaics. The solar cell comprises a silicon substrate with a first surface and a second surface which are opposite to each other in the thickness direction, and the first surface of the silicon substrate sequentially comprises a first tunneling oxide layer, a first lightly doped layer, a first transparent conductive layer, a first heavily doped layer and a first passivation layer from inside to outside, and the doping types of the first lightly doped layer and the first heavily doped layer are the same. The doping layer is divided into the lightly doped layer, the transparent conductive layer and the heavily doped layer, and by means of good conductivity and light transmission of the transparent conductive layer, the passivation performance and low contact resistance of the solar cell are ensured, the negative influence of parasitic current on the cell efficiency is reduced, and the cell efficiency is improved.

The invention discloses a solar cell, a preparation method thereof and a photovoltaic module. The preparation method comprises the following steps: providing a silicon wafer; forming a doping structure on the surface of the silicon wafer; forming a patterned mask on the doped structure; forming a dielectric layer on the surface of the doping structure and the surface of the mask; the mask and the dielectric layer on the surface of the mask are removed, and a window penetrating to the doping structure in the thickness direction of the silicon wafer is formed in the dielectric layer; and preparing an electrode in contact with the doping structure at the window of the dielectric layer. According to the method, the patterned mask is prepared firstly, then the dielectric layer is deposited, and the mask is removed to form the window, so that the damage caused by windowing of the dielectric layer by adopting processes such as laser can be remarkably reduced, the growth of a subsequent electrode is ensured, a metalized structure with excellent electrical performance can be obtained, and the battery efficiency and the module power are improved.

The utility model discloses a solar cell and a solar assembly, relates to the technical field of solar cells, and aims to solve the problem that an area between two auxiliary grids is blackened during EL test. The solar cell comprises a cell piece main body, a first surface electrode structure comprising a first end bus electrode, a second end bus electrode and a first surface collector electrode, and a second surface electrode structure comprising a third end bus electrode, a fourth end bus electrode and a second surface collector electrode. In the second end bus electrodes, the distribution density of the first surface collector electrodes is smaller than the distribution density of the first surface collector electrodes located between the two adjacent second end bus electrodes; in the third end bus electrodes, the distribution density of the second surface collector electrodes is smaller than the distribution density of the second surface collector electrodes located between every two adjacent third end bus electrodes.

The utility model provides a back contact type solar cell, and belongs to the technical field of solar cells. The back contact solar cell includes: a substrate; the doped layer is formed on the substrate and comprises N doped regions and P doped regions which are alternately arranged at intervals; the electrode layer is formed on the doping layer and comprises an N region electrode formed on the N doping region and a P region electrode formed on the P doping region; wherein the P-doped region, the N-doped region, the P-region electrode and the N-region electrode are constructed to meet the size relationship shown in the following formula: 1 / 2gt; a WP electrode / WP region gt; a WN electrode / WN region gt; the width of the WP electrode is equal to the width of the P-region electrode, the width of the WN electrode is equal to the width of the N-region electrode, the width of the WP region is equal to the width of the P-doped region, and the width of the WN region is equal to the width of the N-doped region. The sizes of the P-doped region, the N-doped region, the P-region electrode and the N-region electrode are designed, the passivation effect difference of the N-doped region and the P-doped region can be considered, the contact resistance of the N-doped region and the P-doped region is matched, and the cell efficiency is improved.

The present application relates to the fields of gene therapy and molecular biology. More specifically, the present invention relates to a method for producing a modified adeno-associated virus (AAV) capsid and to a modified AAV capsid produced by said method, as well as to an isolated nucleic acid encoding said modified capsid and a vector based on recombinant adeno-associated virus for delivering a heterologous nucleic acid sequence to a subject, which includes said modified capsid.

The invention discloses a preparation method of a solar cell and the solar cell, and relates to the technical field of solar cells. The preparation method of the solar cell comprises the following steps: forming an oxide layer on a first main surface of a silicon substrate; depositing a doping control layer on the oxide layer; performing gettering treatment on the silicon substrate by combining with the doping control layer, and forming a shallow doping layer on one surface, close to the oxide layer, of the silicon substrate; and removing the doping control layer and the oxide layer. According to the embodiment, the doping control layer is arranged, so that the doping concentration of the shallow doping layer can be controlled, the shallow doping layer with relatively low doping concentration is formed, the technological process of preparing the solar cell is simplified, and the cell performance is improved.

This invention belongs to the field of back-contact battery technology, specifically relating to a back-contact battery and its battery assembly with a specific front-side structure. This specific front-side structure includes a tunneling oxide layer and a specifically doped amorphous silicon layer sequentially disposed on the front side of a silicon substrate. Within the specifically doped amorphous silicon layer, a low-doped amorphous silicon layer, a high-doped amorphous silicon layer, and an oxygen-doped amorphous silicon layer are sequentially disposed along the direction away from the tunneling oxide layer. The specifically doped amorphous silicon layer is doped with phosphorus (P) and contains hydrogen (H). The P doping concentration C1 in the low-doped amorphous silicon layer and the P doping concentration C3 in the oxygen-doped amorphous silicon layer are both lower than the P doping concentration C2 in the high-doped amorphous silicon layer. This specific front-side structure enables the back-contact battery to achieve an absorption rate exceeding 85% for incident light within 400 nm. The back-contact battery of this invention maintains good performance even after long-term exposure to ultraviolet light, improving the battery's UV reliability while achieving high transmittance and high battery efficiency.

The invention relates to the technical field of nano materials, in particular to a defect-rich MoS2 three-dimensional flower-shaped nano material and a preparation method thereof.According to the defect-rich MoS2 three-dimensional flower-shaped nano material and the preparation method thereof, a 1T / 2H coexisting MoS2 nano flower formed by assembling nanosheets is synthesized through an ultrasonic cooperation template-free hydrothermal method, and the MoS2 nano flower is reduced through NaBH4 at the room temperature to synthesize a defect-rich MoS2-x nano sheet flower-shaped structure. On one hand, due to the flower-shaped 1T / 2H nanostructure, the MoS2 nanosheet has relatively high conductivity in a 1T phase and has good stability in a 2H phase; on the other hand, the defect engineering strategy can effectively construct charge redistribution on the MoS2-x nanosheet rich in sulfur defects, the intrinsic conductivity is further improved, electrochemical active sites are increased, the diffusion rate of Zn < 2 + > is increased, and the electrochemical performance is optimized. Research results show that the defect-rich MoS2-x nanosheet obtains the specific discharge capacity of 258.3 mAh.g <-1 > at 0.1 A.g <-1 >, good rate capability and excellent cycling stability (the capacity is kept at 91.3% after 1500 times of cycling).

The invention provides a proton conduction composite membrane for a flow battery and a preparation method thereof, and the method comprises the following steps: dissolving polyvinylidene fluoride and a first modified additive in a first organic solvent, and stirring for the first time to obtain a first membrane casting solution; dissolving polybenzimidazole and a second modified additive in a second organic solvent, and stirring for the second time to obtain a second membrane casting solution; the preparation method comprises the following steps: coating a flat carrier surface with a first membrane casting solution, carrying out tape casting to form a first thin layer, carrying out first-time baking oven heating until the first thin layer is completely dried to obtain a base membrane, coating a second membrane casting solution on the base membrane surface, carrying out tape casting to form a second thin layer, and carrying out second-time baking oven heating until the second thin layer is completely dried. The membrane surface resistance is greatly reduced, the coulombic efficiency of the flow battery is improved, the stable operation life of the flow battery is prolonged, the production cost is low, the technological process is simple and controllable, the membrane performance is stable and reliable, the battery efficiency is remarkably improved, the technical industrialization amplification difficulty is low, and automatic continuous production can be realized.

The present invention belongs to the technical field of back contact batteries, and specifically relates to a back contact battery with improved contact characteristics, a preparation method and an application thereof, wherein at least a portion of the surface layer of a transparent conductive film layer is doped with a metal material to form a doped region, and the average doping concentration of the metal material in the doped region is 1e18cm ‑3 ‑5e22cm ‑3 , the proportion of oxygen vacancies in the transparent conductive film layer to the total oxygen atoms contained is 5%-60%, and doping regions are respectively set on the transparent conductive film layers that the N-type region metal electrode and the P-type region metal electrode contact respectively. The present invention can well match semiconductors with different polarities on the back side, improve the contact characteristics between the metal electrode and the transparent conductive film layer, the transparent conductive film layer and the semiconductor layer, enhance the conductivity of the transparent conductive film layer, reduce the resistivity of the transparent conductive film layer, and reflect the effect of reducing the overall resistance from the macroscopic measurement, thereby improving the battery efficiency.

The invention discloses a perovskite precursor solution, a perovskite active layer prepared from the perovskite precursor solution and application of the perovskite active layer. The perovskite precursor solution contains a mixture of formamidine thiocyanate (FASCN) and rubidium thiocyanate (RbSCN). According to the invention, the mixed additives formamidine thiocyanate FASCN and rubidium thiocyanate RbSCN are added into the precursor solution to effectively promote phase transformation from an inactive phase delta to an active phase alpha, so that the efficiency and the stability of the methylamine-free perovskite battery are remarkably improved, and the methylamine-free perovskite battery has a relatively good commercial application prospect.

The invention discloses a high-efficiency N-type TOPCon battery and a preparation method thereof. The preparation method comprises the following steps: S1, providing an N-type silicon substrate and carrying out alkali texturing; s2, performing chemical vapor deposition on the front surface of the N-type silicon substrate to form a front surface tunneling silicon oxide thin film layer and an amorphous silicon layer; s3, performing low-temperature boron diffusion on the front surface to form a doped amorphous silicon layer; s4, carrying out laser doping on the surface of the doped amorphous silicon layer to carry out crystalline modification to form a laser modified region; s5, polishing the back surface of the N-type silicon substrate; s6, performing low-temperature chemical vapor deposition on the back surface of the N-type silicon substrate to form a back surface tunneling silicon oxide thin film layer, an intrinsic polycrystalline silicon layer and a mask layer; s7, performing low-temperature phosphorus diffusion on the back surface to form a doped polycrystalline silicon layer; s8, removing the mask layer; s9, front and back composite passivation films are respectively deposited on the front and back surfaces of the N-type silicon substrate; and S10, printing silver paste in the laser modification area, sintering to obtain a front grid line, printing silver paste on the back, and sintering to obtain a back grid line.

The invention provides a photovoltaic cell and a preparation method thereof. A photovoltaic cell includes a silicon substrate having opposing substrate front and back sides; the oxide layer and the first doping layer are sequentially located on the front face of the substrate, and the first doping layer comprises polycrystalline silicon; the first intrinsic layer and the second doping layer are located in the first area on the front face of the cell and are sequentially and closely located on the first doping layer, and the second doping layer comprises amorphous silicon or microcrystalline silicon; the second intrinsic layer, the third doped layer and the back transparent conductive film layer are sequentially located on the back of the substrate; the first metal electrodes are located on the front face of the cell, the second metal electrodes are located on the back face of the cell, each first metal electrode is located in a first area of the front face of the cell, no first metal electrode is arranged in a second area, and the second metal electrodes make contact with the back face transparent conductive film layer. According to the photovoltaic cell and the preparation method thereof, the metal contact and conductivity of the front surface of the cell can be optimized, and the cell efficiency is improved.

Embodiments of the present application provide a device and method for producing a battery cell. The device includes: an upsetting mechanism and a moving mechanism, where the moving mechanism is configured to: control the upsetting mechanism to move towards the battery cell along a direction of a central axis of the battery cell, and the battery cell includes a housing and a cover plate, and the housing and the cover plate are connected in a sealing manner and formed with a crimping structure turned outwards; and a surface of the upsetting mechanism facing the crimping structure is provided with at least one protruding structure, and the protruding structure is configured to press the crimping structure towards the direction of the central axis of the battery cell when the moving mechanism controls the upsetting mechanism to move towards the battery cell, so that the crimping structure is inclined towards a direction close to the central axis of the battery cell. The device and method for producing the battery cell in the embodiments of the present application could improve processing efficiency of the battery cell, and improve security of the battery cell.

The invention provides a laminated solar cell with a dual-mode port and a preparation method and application thereof, and belongs to the technical field of solar cells. The laminated solar cell is a two-end laminated solar cell or a four-end laminated solar cell; the laminated solar cell comprises a top cell, a bottom cell and a double-sided conductive grid film located between the top cell and the bottom cell. The double-sided conductive grid film comprises a metal grid and a flexible transparent layer filled into meshes of the metal grid. According to the invention, the double-sided conductive grid film is used as a middle connecting layer, and a selectable port use mode is provided. In the two-end laminated cell, the top cell and the bottom cell can be independently prepared, the cell efficiency is improved, and the preparation period of the two-end laminated cell is saved; in the four-end laminated cell, the top cell has the advantages of light weight, small volume and low cost, and the bottom cell does not need to additionally prepare a metal electrode grid line, so that the problem of large weight of the four-end laminated cell is solved.

This application discloses a solar cell and a photovoltaic module, relating to the field of photovoltaic technology. The solar cell includes a cell substrate and grid lines disposed on the cell substrate. The cell substrate includes a silicon substrate, a doped polycrystalline silicon layer, and a passivation layer, which are stacked. Grid line grooves are formed on the passivation layer, with the bottom of the grid line grooves exposing the doped polycrystalline silicon layer. At least a portion of the edge of the passivation layer adjacent to the grid line groove is warped away from the doped polycrystalline silicon layer to form a warped portion. The grid lines cover and fill the grid line grooves. In the solar cell of this application embodiment, the warped edge of the passivation layer forms a warped portion. On the one hand, this widens the bottom area of ​​the grid line groove, which helps to reduce the contact resistance between the grid lines and the doped polycrystalline silicon layer; on the other hand, it can improve the bonding strength between the grid lines and the cell substrate, reducing the risk of grid line detachment.

The present application belongs to the technical field of solar cells, and relates to a heterojunction solar cell, which comprises, from a light-facing side to a back light-facing side, a first electrode, a first conductive film layer, an N-type semiconductor film layer, an intrinsic film layer, a semiconductor substrate, a tunneling oxide layer, a P-type carbon-doped semiconductor film layer, a high-concentration P-type doped semiconductor film layer, a second conductive film layer, and a second electrode; the first conductive film layer fully covers the N-type semiconductor film layer, and the first electrode is electrically connected to the N-type semiconductor film layer through the first conductive film layer; the second conductive film layer fully covers the high-concentration P-type doped semiconductor film layer, and the second electrode is electrically connected to the high-concentration P-type doped semiconductor film layer through the second conductive film layer. The present application aims to provide a heterojunction solar cell, which can improve the electrical power loss caused by the carrier transmission on the back of the cell and improve the cell efficiency.

The invention discloses a hydrogen fuel cell device. Comprising a proton exchange membrane, a hydrogen side catalyst layer, an oxygen side catalyst layer, a hydrogen side diffusion layer, an oxygen side diffusion layer, a hydrogen side bipolar plate and an oxygen side bipolar plate, wherein the proton exchange membrane is used for isolating and conducting protons; the hydrogen side catalyst layer and the oxygen side catalyst layer are used for improving the electrochemical reaction rate; the insulating layer is used for blocking current conduction between adjacent single battery units; and the sealing device is used for blocking fluid leakage. And stable power output can be realized under various load conditions, the use amount of noble metal is reduced, the hydrogen embrittlement resistance of the hydrogen fuel cell is improved, and the sealing performance of the device is improved, so that the service life is prolonged. The power supply is compact in structure, stable in performance, simple and convenient to maintain, and suitable for various scenes such as traffic, small fixed power supplies and portable equipment.

The present invention discloses a strip-shaped cell, a solar cell, a photovoltaic module and a manufacturing method thereof, wherein the strip-shaped cell has a long side and a short side, and the front of the strip-shaped cell has a front main grid arranged along the edge of the short side. The short sides of the long strip-shaped cell can be overlapped and connected, the welding part can be greatly shortened, and the cell efficiency can be improved.

Embodiments of the present disclosure relate to the field of battery technologies and disclose a cell winding device and method. The cell winding device includes a first cutting unit, a first connection unit, a winding unit, and a second cutting unit. The first cutting unit is configured to perform cutting on an electrode sheet. The first connection unit is adjacent to the first cutting unit, and configured to connect, through a connection tape, adjacent electrode sheets that have been subject to the cutting. The winding unit is configured to perform winding on the adjacent electrode sheets connected through the connection tape and drive, in response to completion of the winding, the electrode sheets that are wound to move, in such a manner that the connection tape corresponds to the second cutting unit. The second cutting unit is configured to perform cutting on the connection tape. With the above scheme, a winding efficiency for a battery cell is improved according to the embodiments of the present disclosure.

The present invention belongs to the technical field of back contact battery, and specifically relates to a combined passivation back contact battery and a post-texturing preparation method thereof, comprising: S102, forming a first semiconductor layer and a mask layer on the back of a silicon substrate in sequence; S103, performing cleaning and texturing to form a texturing surface on the light-receiving surface of the silicon substrate, and the maximum pyramid height of the texturing surface on the light-receiving surface is T1; S104, sequentially forming a passivation layer and an anti-reflection layer on the light-receiving surface of the silicon substrate; S105, forming a second semiconductor opening area; S106, performing cleaning and etching to form a groove structure at least in the second semiconductor opening area on the back of the silicon substrate; S107, depositing a second semiconductor layer on the back, the second semiconductor layer comprising an amorphous passivation layer and a second doped silicon layer. The present invention can reduce the interface contact resistance of the second semiconductor opening area, improve the minority carrier lifetime, and improve the battery efficiency and bifaciality while simplifying the process steps and reducing the material cost.

The invention discloses an alkali polishing additive for silicon wafers. The alkali polishing additive comprises organic amine, a complexing dispersant, inorganic salt and a surfactant. The organic amine is one or more of dichloroaniline, diethanol amine and dimethylamine, and the organic amine is 1-5 parts. The complexing dispersant is one or more of sodium benzoate, sodium alginate and sodium citrate, and the complexing dispersant is 3-8 parts. The inorganic salt is one or more of sodium sulfate, lauryl sodium sulfate, sodium pyrosulfate and sodium tartrate, and the inorganic salt is 1-5 parts. The surfactant is one or more of dodecyl dimethyl betaine, sodium alkyl naphthalene sulfonate and alkyl glycoside, and the amount of the surfactant is 5-8 parts; the additive also comprises deionized water; according to the silicon wafer alkali polishing additive, the organic amine is added, the back polishing effect of the same tower footing is obtained under the condition of low weight loss, the battery efficiency is improved, meanwhile, the additive synthesis device can stir and dissolve all the raw materials evenly, and the alkali polishing additive is obtained.

The invention provides a method for improving passivation contact of the back surface of a TOPCon battery. The method for improving the passivation contact of the back surface of the TOPCon battery comprises the following steps: S1, carrying out alkali texturing treatment on an N-type silicon wafer; s2, carrying out boron diffusion on the silicon wafer, and forming a boron-doped emitter on the front surface; s3, removing borosilicate glass on the back surface and the side surface of the silicon wafer, and carrying out alkali polishing on the back surface of the silicon wafer; and S4, preparing a tunneling oxide layer and a doped amorphous silicon layer on the back surface of the silicon wafer by using a PECVD technology. According to the method for improving the passivation contact of the back surface of the TOPCon battery, the poly-Si in the grid line region is oxidized by laser oxidation after poly, annealing crystallization is performed, and a part of the poly in the non-laser region is corroded and removed by a wet etching method, so that on the premise of satisfying poly passivation, the coverage region and thickness of the poly are reduced, parasitic light absorption is reduced, and the passivation contact of the back surface of the TOPCon battery is improved. And the short-circuit current Isc of the battery is improved, so that the battery efficiency, the back efficiency and the double-sided rate are improved. And meanwhile, the cleaning difficulty after laser oxidation can be reduced.

This application relates to the photovoltaic field, providing a solar cell, a photovoltaic module, and a method for fabricating a solar cell. The solar cell includes: a substrate having a front side and a back side, the back side including a textured region and a flat region adjacent to the textured region, the textured region having a doped surface field, and the doped surface field containing a doped element, which is N-type or P-type; a tunneling dielectric layer located on the flat region of the back side of the substrate; a doped conductive layer located on the surface of the tunneling dielectric layer away from the back side of the substrate, the doped conductive layer containing a doped element, the type of which is the same as the type of which is doped in the doped surface field; and a back electrode, a portion of the bottom surface of the back electrode located within the doped conductive layer and in contact with the doped surface field, which can at least reduce the contact resistance of the solar cell.