584 results about "Sheet resistance" patented technology

The invention discloses a preparation method of a solar cell, and the method comprises the following steps: placing an N-type silicon wafer in a furnace tube of a diffusion furnace, and introducing nitrogen and oxygen into the furnace tube to form a first oxide layer on the surface of the silicon wafer; boron trichloride, oxygen and nitrogen are introduced into the furnace tube, so that a boron diffusion layer is formed on the surface, away from the silicon wafer, of the first oxide layer; introducing nitrogen into the furnace tube, and controlling the temperature of the furnace tube to be a first temperature so as to carry out oxygen-free propulsion of the boron element; introducing nitrogen and oxygen into the furnace tube, and controlling the temperature of the furnace tube to rise from the first temperature to a second temperature so as to carry out aerobic propulsion of the boron element; dry oxygen and wet oxygen are alternately introduced into the furnace tube for multiple times to form a second oxide layer; the temperature in the furnace tube is reduced, and dry oxygen continues to be introduced into the furnace tube; and nitrogen is introduced into the furnace tube, the temperature in the furnace tube is reduced, and boron diffusion of the silicon wafer is completed. According to the preparation method of the solar cell, the silicon wafer can have low surface concentration shallow junctions and uniform sheet resistance.

The invention relates to the technical field of ITO coating materials, and provides a low-sheet-resistance and high-light-transmittance ITO coating film and a preparation method thereof.The preparation method comprises the steps that S1, an yttrium-doped zirconium oxide substrate is prepared; s2, performing surface activation on the yttrium-doped zirconium oxide substrate; s3, performing magnetron sputtering in a radio frequency magnetron sputtering chamber, and forming a layer of ITO film on the surface of the yttrium-doped zirconia substrate; and S4, annealing treatment and gradient cooling treatment are carried out. The epitaxial growth of the ITO coating film is optimized through the prepared yttrium-doped zirconia substrate, and the magnetron sputtering, annealing and gradient cooling processes are combined, so that the microstructure of the film is optimized, the carrier mobility and the uniformity and stability of the film are improved, the grain boundary defect and carrier scattering loss in the ITO coating film are reduced, and the performance of the film is improved. The low sheet resistance and high light transmittance of the ITO coating film are synergistically improved, and the obtained ITO coating film has important application value in the fields of high-performance optoelectronic devices, transparent conductive films and the like.

The invention relates to the technical field of flexible transparent electrodes, in particular to a Cu / Al laminated metal grid flexible transparent electrode and a preparation method thereof. The Cu / Al laminated metal grid flexible transparent electrode comprises a flexible substrate, a copper layer arranged on the flexible substrate and an aluminum layer arranged on the copper layer, and the aluminum layer located on the outer layer spontaneously forms an Al2O3 passivation layer with the thickness of 2-5 nm in air. The Al2O3 passivation layer can effectively prevent oxygen and moisture from permeating inwards, so that oxidation of the copper layer in a humid or high-temperature environment is fundamentally inhibited, long-term stability of the electrical property of the electrode is ensured, and meanwhile, due to the fact that the thickness of the copper layer is 150-250 nm, excellent conductivity is provided, and low square resistance is achieved; the latticed structure maintains high light transmittance of the electrode while ensuring a high conductive path. Finally, the structure has excellent oxidation resistance, high light transmittance, low sheet resistance and flexible stability under the support of a flexible transparent substrate with the thickness of 50-200 [mu] m, and meets the harsh requirements of a new generation of flexible optoelectronic devices on electrode performance.

The invention discloses a dynamic optimization method and system for a boron diffusion process of a photovoltaic cell and electronic equipment. Comprising the following steps: collecting process parameters and sheet resistance data, and associating the process parameters and the sheet resistance data to form a process parameter set; optimizing a process parameter set, removing noise data and incomplete data, and extracting an available feature data set; dividing the feature data set into a training set and a verification set, and training to obtain a nonlinear regression model for predicting resistance data under different feature data; carrying out validity verification on the nonlinear regression model, and constructing an optimization function to reduce a difference value between a predicted value and an actual value; and deploying a nonlinear regression model in the diffusion process, adjusting the process parameters of the diffusion process in real time according to the predicted value, and optimizing the obtained sheet resistance data. The problem that the boron diffusion process is difficult to accurately adjust by a traditional process control method can be solved.

The invention relates to photochromic glass and a vehicle. The photochromic glass comprises two glass substrates and a photochromic assembly clamped between the two glass substrates, the photochromic assembly comprises a photochromic layer, a diffusion ring, a first conductive layer and a second conductive layer, the diffusion ring and the photochromic layer are arranged on the first conductive layer, and the second conductive layer is located on the side, away from the first conductive layer, of the photochromic layer. The diffusion ring is insulated from the color-changing layer and the second conductive layer respectively; the diffusion ring and the second conductive layer are respectively communicated with an external circuit so as to form a voltage difference between the first conductive layer and the second conductive layer to change the color of the color changing layer, the diffusion ring surrounds the periphery of the color changing layer, and the conductive sheet resistance of the material of the diffusion ring is smaller than that of the material of the first conductive layer. According to the photochromic glass, the diffusion time of the current in the first conductive layer is shortened through the diffusion ring, so that the current of an external circuit can be diffused to the photochromic layer more quickly, and the response speed of the photochromic glass is increased.

The application relates to the technical field of display panels, and discloses a display panel, a display screen and electronic equipment. The CGL of the display panel comprises N-CGL, i-CGL and P-CGL which are stacked in sequence. The LUMO energy level of the organic material corresponding to the i-CGL is less than or equal to -3.5 eV, and the work function of the inorganic material corresponding to the i-CGL is greater than or equal to 3.5 eV. In particular, the Fermi energy level of the i-CGL is lower than that of the P-CGL host material, and the thickness of the i-CGL can be any value less than or equal to 15 nm (especially less than 5 nm). In this case, the charge generation capability of the N-CGL, the i-CGL and the P-CGL in the direction parallel to the thickness of the CGL is improved, the sheet resistance in the direction perpendicular to the thickness of the CGL is greater than 1 GΩ / Dia, the sub-pixel can realize high-efficiency and low-power-consumption light emission, the voltage value obtained by voltage division from the driving voltage of another sub-pixel is small, and the crosstalk between the sub-pixels is reduced or even eliminated.

The invention discloses a high-voltage bidirectional silicon controlled rectifier electrostatic protection device and a manufacturing method. The high-voltage bidirectional silicon controlled rectifier electrostatic protection device comprises a P-type substrate, a P-type well and a high-voltage N well, the emitter P + injection of a parasitic PNP triode and the emitter N + injection of a parasitic NPN triode in the P-type well are arranged alternately, so that the length of a transverse discharge path of the silicon controlled rectifier is reduced to the greatest extent, the square resistance of a PNPN positive feedback conduction path is greatly reduced, and the key problem that a symmetrical bidirectional silicon controlled rectifier structure cannot be effectively opened in a high-voltage window of more than 70V is solved; in addition, the layout can provide an additional parasitic NPN triode path for a silicon controlled rectifier path, the effective area of an emitter of the parasitic NPN triode and the proportion of the emitter in a silicon controlled rectifier loop are increased, and the current discharge capacity of the device is further improved. Therefore, reference can be provided for the structural design of the high-voltage symmetrical bidirectional silicon controlled rectifier electrostatic protection device, and the silicon controlled rectifier can be effectively applied to ESD protection of a high-voltage bidirectional port.

The invention relates to an electric heating anti-icing multi-layer structure based on a copper-clad PI film and graphene. The electric heating anti-icing multi-layer structure sequentially comprises a surface insulating layer, an adhesive film layer, a graphene heating layer, an adhesive film layer and a surface insulating layer, and the graphene heating layer is provided with a copper-clad PI film layer. The method comprises the following steps: etching a copper foil on a polyimide film to obtain an etched copper electrode film; the preparation method comprises the following steps: uniformly dispersing graphene and polyimide resin through vacuum stirring, coating the surface of a polyimide electrode film with the graphene and polyimide resin through a tape casting method, and performing high-temperature curing to obtain a graphene heating layer with smooth appearance and uniform sheet resistance; and molding the heating layer and the composite material through an autoclave to obtain the wing-shaped electric heating anti-icing assembly.

The invention discloses a solar single-crystal efficient TOPCon + SE battery piece ultrahigh sheet resistance diffusion process which mainly comprises a front boron process, an SE process and a rear oxidation process, and the front boron process comprises high-temperature oxidation before diffusion and a diffusion process composed of three-step diffusion and heating propulsion. According to the invention, a layer of SiO2 can be coated on the surface of the silicon wafer through high-temperature oxidation before diffusion and is used as an anti-reflection film layer; the PN junction is prepared by adopting a step-by-step diffusion method, so that the advantage of good junction uniformity can be realized, boron can be uniformly distributed on the surface of a silicon wafer through a specific boron diffusion method, and meanwhile, boron elements can be better deposited on the surface of the silicon wafer through variable-temperature diffusion and propulsion; by adding the SE process, the square resistance can reach 700-800 ohms, the junction depth in the grid line area is deeper, the increase of ohms becomes better, the cell center recombination is reduced due to the lower surface concentration, and the open-circuit voltage of the cell is improved; and the post-oxidation process has an annealing effect and can repair lattice damage and the like.

A unit cell of a metamaterial absorber may be an electromagnetic wave absorber for a 5.8 GHz band or 10 GHz band. The unit cell of the metamaterial absorber may include a first metal layer including at least one concentric circular ring-shaped conductor pattern, a first intermediate layer disposed on the lower surface of the first metal layer and composed of polyimide, a resistive layer disposed on the lower surface of the first intermediate layer, a second intermediate layer disposed on the lower surface of the resistive layer and composed of polyimide, and a second metal layer disposed on the lower surface of the second intermediate layer. The resistive layer may increase the operating bandwidth of an operating frequency. The thickness of the resistive layer may be 0.05 mm to 0.15 mm. The sheet resistance of the resistive layer may be 530 Ω·sq−1 to 550 Ω·sq−1.

The invention belongs to the field of optoelectronic materials, and provides a dielectric / metal / dielectric multilayer transparent electrode material which sequentially comprises a substrate, a dielectric layer 2, a metal layer and a dielectric layer 1, the material of the dielectric layer 2 comprises metal oxide doped zinc oxide a; the material of the dielectric layer 1 comprises metal oxide doped zinc oxide b; furthermore, the metal oxide doped zinc oxide a and the metal oxide doped zinc oxide b are respectively and independently selected from one or more of aluminum oxide doped zinc oxide and tin oxide doped zinc oxide. Correspondingly, the invention also provides a preparation method of the dielectric / metal / dielectric multilayer transparent electrode material. Compared with a conventional dielectric / metal / dielectric multilayer transparent electrode material, the dielectric / metal / dielectric multilayer transparent electrode material disclosed by the invention is obviously more stable in photoelectric property, and the sheet resistance stability of the dielectric / metal / dielectric multilayer transparent electrode material is obviously improved especially in a high-temperature and high-humidity environment.

Microbial activity can be mitigated or prevented by applying an antimicrobial article to an object to inhibit the transfer of microbial life from the object to anyone thereafter touching the object. The antimicrobial article has a non-electrically conductive substrate comprising first and second opposing surfaces; a catalytic ink disposed as a pattern on the first opposing surface, which catalytic ink pattern comprises multiple unconnected features; and a pattern of electrolessly plated copper metal of unconnected copper metal features that is disposed in registration with the catalytic ink pattern. This antimicrobial article exhibits a sheet resistivity of more than 1,000 ohms / □ as determined using a four-point probe and a source meter.

The invention discloses a honeycomb structure wave-absorbing composite material based on resistive films and a preparation method thereof. The honeycomb structure wave-absorbing composite material comprises a glass fiber board skin layer, a first resistive film layer, a first honeycomb dielectric layer, a second resistive film layer, a second honeycomb dielectric layer, a third resistive film layer and a metal backboard. All the layers are connected through a bonding layer. According to the honeycomb structure wave-absorbing composite material based on the resistive film and the preparation method thereof, the sheet resistance in the first resistive film layer, the second resistive film layer and the third resistive film layer is controllable and customizable, so that impedance matching can be regulated and controlled by regulating and controlling the sheet resistance gradient of the resistive film, the process parameters are more stable, the broadband (2-18GHz) wave-absorbing performance is good, and the application prospect is wide. The first honeycomb dielectric layer and the second honeycomb dielectric layer do not need secondary processing, so that the wave-absorbing performance is endowed, and the resistive film is easy to prepare; in addition, the wave-absorbing composite material prepared by the invention is thin in structural material thickness, light in weight, capable of effectively absorbing a wide frequency band and easy to process.

According to the manufacturing method, through a Roll to Roll continuous production mode, traditional 19 procedures are reduced to 12 procedures, the production speed is increased to 5 m / min, the dielectric constant of a composite PI film doped with nanometer aluminum oxide is smaller than or equal to 3.2 and is reduced by 15% compared with that of a traditional PI film, a micro-arc oxidation insulating layer of copper / magnesium alloy foil is combined, the signal loss of the antenna in the frequency band of 28-300 GHz is reduced by 30%, and the antenna performance is improved. The sheet resistance of the graphene / silver nanowire composite conductive adhesive is smaller than or equal to 0.1 omega / sq, the bending life is larger than or equal to 100,000 times, the performance is improved by 10 times compared with that of traditional silver paste, the long-term dynamic use requirement of wearable equipment is met, no chemical etching liquid is used in the whole process, waste is subjected to magnetic separation and low-temperature pyrolysis, waste discharge is reduced by 90% compared with a traditional process, and the graphene / silver nanowire composite conductive adhesive is environmentally friendly. The carbon-based particles generated through pyrolysis meet the RoHS standard and can be directly used for 3D printing consumables, the antenna produced through the method can adapt to the leading-edge fields of 6G base stations, flexible intelligent watches, implantable medical sensors and the like, and the technology of the Internet of Things and high-frequency communication is promoted.

The invention relates to a preparation method of a visible and near-infrared dual-band high-transmittance transparent conductive film, which is characterized by comprising the following steps of: (1) preparing an ITO (Indium Tin Oxide) film on a transparent substrate by adopting a magnetron sputtering process, and sputtering and depositing the ITO film with the thickness of 200-1000nm; and (2) placing the substrate on which the ITO film is deposited in a high-temperature furnace for rapid heating heat treatment, and cooling after heat treatment. The preparation method has the advantages that the preparation method is simple, and rapid batch production can be realized in combination with an existing magnetron sputtering system; the average transmittance of the transparent conductive thin film prepared by the method reaches 70%-75.1% at the wave band of 1.1-2.5 microns, the average transmittance of the visible light wave band is not lower than 84%, and the sheet resistance is 20-35 omega / sq.

The invention discloses weldable low-temperature sintered silver paste which is prepared by mixing 65-90 parts of micro-nano silver powder, 10-20 parts of metal salt additive, 1-5 parts of polymer additive, 15-19 parts of organic solvent and 1-5 parts of organic additive, the micro-nano silver powder is obtained by mixing nano silver powder with the particle size of 10-50nm and micron silver powder with the particle size of 1-10mu m, and a preparation method comprises the following steps: step 1, preparing a first-stage polymer carrier; the preparation method comprises the following steps: 1, preparing a first-stage polymer carrier, 2, preparing a second-stage polymer carrier, 3, pretreating micro-nano silver powder, and 4, preparing conductive silver paste. Through micro-nano silver powder grading, nano-particles are filled in gaps of micro-particles, the stacking density is improved, the sheet resistance is reduced, an oxidation film is formed on the surface of the passivated micro-nano silver powder, the interface bonding strength can be effectively improved, the sintering activation energy of silver is reduced by the metal salt additive, and by combining the'etching-remelting 'effect of the oxidation film on the surface of the silver powder, the bonding strength of the surface of the silver powder is improved. The sintering temperature is effectively reduced.

The invention discloses a preparation method of a TCO film with good electroplate liquid corrosion resistance, which comprises the following steps: weighing ABCD powder according to the mass percentage, mixing the ABCD powder, grinding, carrying out compression molding, carrying out cold isostatic pressing molding, sintering in a high-temperature atmosphere and the like to obtain a target material, and carrying out sputtering coating by using the target material through a direct-current magnetron sputtering coating machine to obtain the TCO film. The TCO thin film prepared by the method has good electroplate liquid corrosion resistance, low resistivity and good conductivity, the sheet resistance of the thin film is only slightly increased and the transmittance is only slightly reduced after the thin film is soaked for 10 minutes, and the TCO thin film shows excellent electroplate liquid corrosion resistance, is used as an electrode material of a novel crystalline silicon heterojunction solar cell and has good application prospects. The TCO thin film electroplating copper electrode is used for replacing a traditional silk-screen printing silver paste electrode, complete silver removal is achieved, and the non-silicon cost of a heterojunction cell is reduced.

The invention discloses an N-type TOPCON battery and a manufacturing method of a high-sheet-resistance low-wet-weight back grid line of the N-type TOPCON battery. The preparation method comprises the steps of adopting selected silver paste to form a grid line precursor and sintering the grid line precursor to form a grid line. Wherein the selected silver paste comprises silver powder, a glass material and an organic carrier; the glass frit includes a primary glass system including a tellurium-lead-lithium oxide and a secondary glass system including oxides of a plurality of selected metals. The preparation method provided by the invention is matched with a corresponding high sheet resistance process of a solar cell manufacturer, a wider sintering window and good efficiency performance can be obtained under the condition of reducing the wet weight, and meanwhile, a good narrow linewidth printability system, an excellent sintering window and good printing capability are achieved.

A back-contact cell and a preparation method therefor, and a cell module, which belong to the technical field of back-contact cells. The back-contact cell comprises: a silicon wafer, which has a front surface and a back surface; and first semiconductor layers and second semiconductor layers, which are disposed on the back surface and are alternately arranged in the Y-axis direction of the silicon wafer. The back-contact cell further comprises a silicon alloy layer and a metal conductive layer, which are sequentially disposed outwards in the Z-axis direction of the silicon wafer, wherein the silicon alloy layer is disposed on the outer surfaces of the second semiconductor layers and extends to the outer surfaces of adjacent first doped silicon crystal layers; and the sheet resistance of the silicon alloy layer is 60-100 Ω / □, and the sheet resistance of the metal conductive layer is 3-50 Ω / □. In the back-contact cell, it is unnecessary to additionally provide a transparent conductive film layer, fingers and busbars, and the manufacture procedure is simpler; in addition, the use of expensive low-temperature silver paste and transparent conductive film layers is not required, thereby significantly reducing the production costs of the cell, and also ensuring excellent cell conversion efficiency.

The invention belongs to the technical field of heterojunction bipolar transistors, and particularly relates to a heterojunction bipolar transistor and an MOCVD epitaxial growth method thereof. The heterojunction bipolar transistor provided by the invention comprises a transition layer arranged between a base region and an emission layer, and the MOCVD epitaxial growth method comprises the step of growing the transition layer on the surface of the base region by adopting a linear variable-temperature staged pulse metal organic chemical vapor deposition method, pH3 is continuously introduced within the total growth time of the linear variable-temperature staged pulse metal organic chemical vapor deposition method, and trimethyl indium, trimethyl gallium and silane are introduced in a single-cycle staged pulse manner; and the temperature of the reaction chamber is linearly increased from the base region growth temperature to the emission layer growth temperature within the time from the T1 initial moment to the TN initial moment. The heterojunction bipolar transistor obtained by the method provided by the invention is large in gain, low in sheet resistance and good in reliability.

The utility model discloses a boron diffusion reaction intake system and reaction equipment, the boron diffusion reaction intake system comprises a boron source intake assembly and a reaction intake assembly, the boron source intake assembly comprises a first intake pipe, a first intake port is used for introducing a boron source, the first intake port is used for directly communicating with a reaction cavity, and the reaction intake assembly comprises a second intake pipe; the reaction gas inlet assembly comprises at least one second gas inlet pipe, a second gas inlet is used for introducing oxygen or nitrogen, and the second gas inlet pipe is isolated from the first gas inlet pipe; the reaction equipment comprises the boron diffusion reaction gas inlet system. According to the utility model, the first gas inlet pipe and the second gas inlet pipe are isolated from each other, and a boron source and other reaction gases are respectively fed through the first gas inlet pipe and the second gas inlet pipe, so that the boron source gas and oxygen are prevented from being mixed outside the reaction cavity, and the possibility that the boron source gas and the reaction gases react in advance before entering the reaction cavity is reduced; the influence of a gas inlet mode on a gas field in the reaction cavity is reduced, and the uniformity of sheet resistance of the silicon wafer is improved.

The invention provides a preparation method of a doped polycrystalline silicon layer and a preparation method and application of a TBC battery, and relates to the technical field of solar cells, and the preparation method comprises the following steps: depositing the doped polycrystalline silicon layer on a tunneling oxide layer, and then annealing; wherein deposition of the doped polycrystalline silicon layer and annealing serve as one procedure, the process of preparing the doped polycrystalline silicon layer comprises at least two procedures, the annealing temperature in each procedure is lower than the deposition temperature, and the deposition temperatures in the adjacent procedures are decreased progressively. And the cell conversion efficiency is improved.

The invention provides a porous composite current collector and a preparation method thereof, the porous composite current collector comprises a base film layer and a conductive layer arranged on the surface of the base film layer, the conductive layer comprises a conductive material, the base film layer comprises a high-molecular polymer, the base film layer is provided with a plurality of through holes, and the through holes are communicated with the conductive material. And a blocking part for preventing magnetron sputtering pollution is arranged in the through hole. By effectively optimizing the composition and the preparation process of the porous composite current collector, the sheet resistance of the porous composite current collector is reduced, and the situation that a conductive material is hit onto a sputtering back roller through vertical holes to cause back roller pollution is avoided, so that the porous composite current collector has high conductivity and high compression strength, and the binding force of a conductive layer and a base film layer is improved.

The invention relates to a composite current collector and a preparation method and application thereof. The composite current collector comprises a polymer-based film layer and a metal layer arranged on at least one surface of the polymer-based film layer, wherein the polymer-based film layer comprises a metal embedded layer in contact with the metal layer; and the strength factor # imgabs0 # of the composite current collector is # imgabs1 # and # imgabs2 #. The strength factor of the composite current collector is regulated and controlled within a certain range, so that the tensile strength of the composite current collector can be obviously improved relative to the tensile strength of a base film. In addition, the composite current collector provided by the invention also has good peel strength and low sheet resistance.

The invention belongs to the technical field of organic functional materials and organic electronics, and particularly relates to a modified stretchable electrode and a preparation method and application thereof. Silver nanowire dispersion liquid is spin-coated on a substrate, an obtained silver nanowire film is patterned, the obtained patterned silver nanowire film is soaked in a modifier (a small molecule compound containing a group capable of being combined with silver and a hydrogen supply group) for modification, the upper portion of the obtained modified silver nanowire film is coated with an organic polymer solution, and after annealing, the silver nanowire film is obtained. And stripping from the substrate to obtain the modified stretchable electrode. Through the interaction between the modified and enhanced silver nanowire film and the organic polymer, the tensile property is improved, the situation that the sheet resistance of the modified stretchable electrode is increased due to breakage of the silver nanowires is avoided, and the modified stretchable electrode has high conductivity, high transparency and high fatigue resistance at the same time.

The present invention discloses an electromagnetic shielding material, a film and a preparation method thereof, wherein the electromagnetic shielding material comprises an A-MXene material, wherein there are bonding points or bonding segments of M-A-M between MXene sheets of the A-MXene material, wherein the A is selected from at least one of elements of group VIIB, VIII, IB, IIB, IIIA, IVA, VA or VIA, and the M represents a transition metal element in the MXene sheet; the preparation method of the electromagnetic shielding material comprises: reacting an initial MXene material with a single substance or compound of A at a predetermined temperature for a predetermined time; the initial MXene material is a MXene material containing a Cl, a Br or an I functional group. The present invention aims at the technical problem that the MXene material containing a Cl functional group has high resistance when applied to the field of electromagnetic shielding, and increases interlayer bonding points or bonding segments of A atoms between MXene sheets to obtain a novel electromagnetic shielding material having both excellent stability and low sheet resistance characteristics.

The invention belongs to the technical field of new materials, and discloses a layered double hydroxide film for alkaline water electrolysis, and the layered double hydroxide film is obtained by connecting layered double hydroxide particles into a continuous film by using polytetrafluoroethylene as an adhesive. According to the invention, polytetrafluoroethylene (PTFE) is used as an adhesive, and layered double hydroxide (LDH) particles are connected into a continuous compact film by a calendering method. The preparation method does not need or rarely needs to use an organic solvent, and is easy for continuous industrial production. When the prepared layered double hydroxide film is used for alkaline water electrolysis, the sheet resistance and hydrogen permeability which are obviously lower than those of a commodity Zirfon film are shown, and the layered double hydroxide film can be widely applied to industrial production and has relatively high ionic conductivity.

The invention belongs to the technical field of lithium ion batteries, and particularly relates to a preparation method and application of a carbon-containing lithium iron phosphate positive electrode material. The preparation method of the carbon-containing lithium iron phosphate positive electrode material provided by the invention comprises the following steps: (1) mixing a lithium source, an iron source, a phosphorus source and a carbon source, and sintering in an inert atmosphere to obtain precursor powder; (2) mixing the precursor powder, a conductive agent and a dispersing agent, and filtering to obtain a mixed material; and (3) drying the mixed material, grinding and sieving to obtain the carbon-containing lithium iron phosphate positive electrode material. According to the method, the carbon-containing lithium iron phosphate precursor and the conductive agent are mixed to prepare the positive electrode material, so that the use amount of the conductive agent is reduced, the processing performance of slurry is improved, the distribution uniformity of the conductive agent is improved, the conductivity among particles is enhanced, the sheet resistance of a positive plate is reduced, the conduction path of Li < + > is shortened, and the electrochemical performance of the positive electrode material is improved.

The invention provides a positive electrode composite current collector, a positive electrode plate, a secondary battery and an electric device. The positive electrode composite current collector comprises a polymer supporting layer, a conductive layer and a high-resistance layer, and the conductive layer is arranged on at least one surface of the polymer supporting layer; the high-resistance layer is arranged on the surface, away from the polymer supporting layer, of the conducting layer, the resistivity of the high-resistance layer is higher than that of the conducting layer, the total sheet resistance of the high-resistance layer and the conducting layer is R1, and R1 is larger than or equal to 50 m omega / -and smaller than or equal to 80 m omega / -. The positive electrode composite current collector disclosed by the invention can keep normal electrode conductivity, so that the DCR of the battery is in a proper range; therefore, the battery has a high nail penetrating test passing rate, and the safety performance of the battery is improved.

The invention provides a solar cell and a preparation method thereof, and a photovoltaic module, the solar cell comprises a silicon substrate, and the back surface of the silicon substrate comprises first doped regions and second doped regions which are alternately arranged along the horizontal direction of the silicon substrate; the first doped region corresponds to the P-type doped layer, the doping concentration of the first doped region is 1 * 10 < 15 > atom / cm < 3 > to 1 * 10 < 18 > atom / cm < 3 >, and the sheet resistance is 500-2000 omega / sq; the second doped region corresponds to the N-type doped layer, the doping concentration of the second doped region is 1 * 10 < 15 > atom / cm < 3 > to 1 * 10 < 18 > atom / cm < 3 >, and the sheet resistance is 500-2000 omega / sq; and the first passivation layer is positioned on the surfaces of the P-type doped layer and the N-type doped layer. The first doped region and the second doped region have the characteristics of low doping concentration and high sheet resistance, so that the photoelectric conversion efficiency of the solar cell is improved.