37results about How to "Low ionic conductivity" patented technology

A rechargeable lithium cell comprising a cathode having a cathode active material, an anode having an anode active material, a porous separator electronically separating the anode and the cathode, a non-flammable quasi-solid electrolyte in contact with the cathode and the anode, wherein the electrolyte contains a lithium salt dissolved in a first organic liquid solvent with a concentration sufficiently high so that the electrolyte exhibits a vapor pressure less than 0.01 kPa when measured at 20° C., a flash point at least 20 degrees Celsius higher than the flash point of the first organic liquid solvent alone, a flash point higher than 150° C., or no flash point. This battery cell is non-flammable and safe, has a long cycle life, high capacity, and high energy density.

A method of producing a pre-sulfurized active cathode layer for a rechargeable alkali metal-sulfur cell; the method comprising: (a) Preparing an integral layer of meso-porous structure of a carbon, graphite, metal, or conductive polymer having a specific surface area greater than 100 m²/g; (b) Preparing an electrolyte comprising a solvent and a sulfur source; (c) Preparing an anode; and (d) Bringing the integral layer and the anode in ionic contact with the electrolyte and imposing an electric current between the anode and the integral layer (serving as a cathode) to electrochemically deposit nano-scaled sulfur particles or coating on the graphene surfaces. The sulfur particles or coating have a thickness or diameter smaller than 20 nm (preferably <10 nm, more preferably <5 nm or even <3 nm) and occupy a weight fraction of at least 70% (preferably >90% or even >95%).

A rechargeable lithium-sulfur cell comprising a cathode, an anode, a separator electronically separating the two electrodes, a first electrolyte in contact with the cathode, and a second electrolyte in contact with the anode, wherein the first electrolyte contains a first concentration, C₁, of a first lithium salt dissolved in a first solvent when the first electrolyte is brought in contact with the cathode, and the second electrolyte contains a second concentration, C₂, of a second lithium salt dissolved in a second solvent when the second electrolyte is brought in contact with the anode, wherein C₁ is less than C₂. The cell exhibits an exceptionally high specific energy and a long cycle life.

The invention provides solid electrolyte of a lithium ion battery and a preparation method of the solid electrolyte as well as the lithium ion battery. The solid electrolyte of the lithium ion batterycomprises a core material and a shell material coating the outer surface of the core material; the core material comprises Li1+xMxTi2-x(PO4)3, wherein M is selected from at least one of Al, La, Cr, Ga, Y or In, and 0.05fx f0.4; the shell material comprises Li0.6+yB0.8SiyP1-yO4, wherein 0.01fy f0.5; the Li 0.6+yB0.8SiyP1-yO4 shell material makes full surface contact with the core material, so thatthe ability of resistance between grains of the core material is obviously reduced; in addition, the solid electrolyte of the lithium ion battery has lower electronic conductivity and a complete anddense electronic shielding layer is formed on the surface of the core material, so that the problem that Ti<4+> is reduced into Ti<3+> is better solved. The prepared solid electrolyte has the characteristics of a wide electrochemical window (the electrochemical window is greater than 5V), relatively-high ionic conductivity and low electronic conductivity.

The invention relates to a lithium-air battery structure, including a lithium negative electrode, a porous diaphragm and a positive electrode which are sequentially laminated, an electrically conductive porous function layer is arranged between the lithium negative electrode and the porous diaphragm, the electrically conductive porous function layer is an electrically conductive porous carbon material layer or a composite layer of an electrically conductive porous carbon material and catalytic components, and mass ratio of electrically conductive porous carbon material to other functional components is 20:1 to 2:1. By the electrochemical reaction of the conductive porous functional layer and dissolved diffused oxygen or reactive oxygen species, the dissolved diffused oxygen or reactive oxygen species can be effectively consumed, the corrosion and damage to the lithium negative electrode can be reduced, and substantial improvement of the battery stability can be facilitated.

The invention discloses a solid thin film electrolyte material and a preparation method thereof. The solid thin film electrolyte material has a structure as shown in the formula: Li-(Mn1-Xm1x)-(Til-yM2y)-O, wherein, 0<=x<=1, 0<=y<=1, M1 is selected from at least one of La, Sr, Na, Nd, Pr, Sm, Gd, Dy, Y, Eu, Tb and Ba, and M2 is selected from at least one of Mg, W, Al, Ge, Ru, Nb, Ni, Ta, Co, Fe, Zr, Hf, Fe, Cr and Ga. The solid thin film electrolyte material is obtained by using a sol-gel method or radio frequency magnetron sputtering method. The solid thin film electrolyte material has relatively high Li ion conductivity, relatively low electron conductivity and favorable thermodynamic stability, and is particularly suitable for producing solid lithium ion batteries.

A nonaqueous solvent that includes an ionic liquid and has at least one of the following characteristics: high lithium ion conductivity, high lithium ion conductivity in a low temperature environment, high heat resistance, a wide available temperature range, a low freezing point (melting point), low viscosity, and the like. The nonaqueous solvent includes an ionic liquid and a fluorinated solvent. The ionic liquid contains an alicyclic quaternary ammonium cation which has a substituent and a counter anion to the alicyclic quaternary ammonium cation which has the substituent.

The invention discloses a negative-pole active material. The negative-pole active material comprises a core material and a cladding material formed outside the core material, wherein the cladding material is constituted by a first material and a second material cladding outside the first material, and the first material can form an alloy with lithium; ionic conductance of the second material is 10<-5>-10<-4>S/cm, electronic conductivity is lower than 10<-10>S/cm. In addition, the invention discloses a preparation method of the negative-pole active material and a lithium ion battery using the negative-pole active material. The negative-pole active material has the advantages that the cycle performance and charge-discharge efficiency of a lithium ion battery is improved, and the service life of the battery is prolonged.

The invention discloses a practical carbon dioxide reduction film electrolyzer and a preparation method thereof, and belongs to the field of electrocatalytic carbon dioxide reduction. The film electrolyzer comprises a cathode flow field plate, a cathode gasket, a cathode diffusion layer, a membrane electrode, an anode diffusion layer, an anode gasket and an anode flow field plate which are assembled in sequence, wherein the membrane electrode comprises an SPE membrane, a cathode catalyst and an anode catalyst, the cathode catalyst and the anode catalyst are located on the two sides of the SPEmembrane respectively, the cathode flow field plate is smooth in a snake shape, and the anode flow field plate is a net-shaped flow field. The method is simple and safe to operate, the electrolyzer works efficiently and stably, the performance of the electrolyzer reaches a high level in the same field, for example, hundreds of milliamperes of current density can be achieved through a low cell voltage, the selectivity exceeds 90%, and the like, and the electrolyzer has novelty, practicability and wide prospects.

The invention discloses lithium-ion battery electrolyte. The electrolyte comprises LiPF6, a non-aqueous organic solvent and additives, wherein the additives comprise fluoroalkenyl phosphate compounds and LiBOB, the structural general formula of the fluoroalkenyl phosphate compounds is the general formula I or the general formula II shown in the specification; according to the general formula, when R1 represents alkyl with 1-5 carbon atoms, R2 represents fluoroalkenyl, and when R1 represents fluoroalkyl, R2 represents any one of alkenyl with 2-5 carbon atoms and fluoroalkenyl with 2-5 carbon atoms. The flammability of the lithium-ion battery electrolyte is low, the gas production capacity of the lithium-ion battery prepared from the electrolyte is small in the charging and discharging processes, and the battery can be effectively prevented from expanding and has excellent high-temperature cycle performance.

The invention provides a negative electrode surface protection method suitable for a solid-state lithium battery and a secondary lithium battery. The negative electrode surface protection method comprises the following steps: adding a polymer or a composite material into an organic solvent to prepare a thin film solution; coating the film solution on the surface of a substrate, and volatilizing and drying for a period of time to obtain a polymer film; transferring the polymer film to the surface of a metal lithium negative electrode; sequentially adding a lithium salt and an additive into an organic solvent according to a certain proportion to prepare an infiltration solution; and coating the metal lithium negative electrode of which the surface is coated with the polymer film with the infiltration solution, infiltrating for a period of time, removing the redundant infiltration solution on the metal lithium negative electrode, and drying for a period of time to obtain the protection layer. The invention has the beneficial effects that the interface side reaction can be effectively inhibited, the current density of the surface of the metal lithium negative electrode is uniform, the generation condition of lithium dendrites in the charging and discharging process is improved, and the cycling stability of the metal lithium negative electrode is improved.

The invention discloses a method for preparing Fe-element doped barium cerate solid electrolyte by using a sol-gel self-combustion method and relates to the technical field of solid electrolyte material preparation. The method comprises the following steps: dissolving cerous nitrate, barium nitrate and ferric nitrate into distilled water according to a BaCe1-xFexO3-x metal element ratio, and conducting uniform stirring so as to obtain a mixed solution; adding citric acid and ethylene glycol into the mixed solution, weighing the components, and uniformly stirring the components in the mixed solution; adjusting the pH value of the system, conducting heating stirring so as to obtain foamed gel, and drying the gel so as to obtain dry gel; putting the dry gel into a muffle furnace, heating andpresintering the dry gel, and keeping the temperature so as to obtain presintered loosened powder; and grinding the presintered loosened powder into fine powder, adding an adhesive into the fine powder, conducting tabletting, and finally conducting sintering. A series of electrolyte materials prepared by using the method have good and low conductive activation energy and ion conductivity and havegood electrolyte material properties, and feasibility of a Fe-element doped barium cerate-based electrolyte material is proved.

The invention relates to a solid electrolyte material, and a preparation method and application thereof. The chemical general formula of the material is LiaREXbFc, wherein RE is at least one of rare earth elements Y, Er and Yb, X is one or two of Cl and Br, 2.5 <= a <= 3.5, 3.5 <= b < 6.5, and 0 < c <= 2. The material improves the performance of the rare earth halide solid electrolyte material, and especially improves the electrochemical oxidation potential and air stability of the rare earth halide solid electrolyte material.

The invention provides a lithium-sulfur battery modified diaphragm and a preparation method thereof, the modified diaphragm comprises a diaphragm matrix, the surface of the diaphragm matrix is coated with a conductive coating, and the conductive coating comprises a conductive skeleton and a polysulfide adsorbent and a catalyst loaded on the conductive skeleton; and the conductive skeleton is mainly prepared from a zero-dimensional conductive carbon material, a one-dimensional conductive carbon material and a two-dimensional conductive carbon material, and has a microporous structure. The preparation method comprises the following steps: uniformly mixing a polysulfide adsorbent, a zero-dimensional conductive carbon material, a one-dimensional conductive carbon material, a two-dimensional conductive carbon material, a catalyst, a high-molecular polymer, pure water and a polar organic solvent to obtain modified diaphragm slurry, coating a diaphragm substrate with the modified diaphragm slurry to obtain a coated diaphragm, transferring the coated diaphragm into pure water, and drying the coating diaphragm from which the solvent is removed. According to the modified diaphragm for the lithium-sulfur battery, the migration path of polysulfide can be prolonged, shuttling of the polysulfide in the diaphragm for the lithium-sulfur battery can be effectively inhibited, and the cycle performance of the lithium-sulfur battery is improved.

The invention belongs to the field of metallurgy, and particularly relates to a molten steel dearsenication fluxing agent, and a preparation method and application method thereof. The molten steel dearsenication fluxing agent comprises the following components in percentage by mass: 88-95% of CaO, 5-12% of Li2O and the balance (0-5%) of impurity. After the molten steel is subjected to pre-deoxidation and desulfurization, [O] and [S] in the molten steel are respectively lowered to 0.001%; the dearsenication fluxing agent and aluminum-calcium alloy are added into a ladle together, wherein the addition amount of the dearsenication fluxing agent is calculated according to the principle that 10Kg of dearsenication fluxing agent can lower the arsenic content in every 100 ton of molten steel by 0.01%, and the addition amount of the aluminum-calcium alloy is 50 wt% of the dearsenication fluxing agent; and after dearsenication, the arsenic content in the molten steel is lowered to 0.001% below. Compared with the prior art, the dearsenication fluxing agent has the advantages of high dearsenication capacity, no pollution and high resource utilization ratio, and the dearsenication product does not pollute the molten steel, thereby solving the key problems in the existing dearsenication technique.

The invention provides a current collector modification method, and a modified current collector and application thereof. The method comprises the following steps: mixing metal oxide powder with alkali metal amino salt, conducting heating to 280-350 DEG C under the condition of protective gas, and carrying out heat preservation for 3-6 hours to implement a nitridation reaction so as to obtain metal nitride; preparing turbid liquid from the metal nitride; and placing a foam metal current collector into the turbid liquid, conducting heating to 50-80 DEG C under the condition of protective gas or vacuum used by the nitridation reaction, and keeping the temperature for 10-20 minutes so as to allow the nitride to be loaded on the foam metal, thereby finishing the modification of the current collector. According to the nitride modified current collector provided by the invention, in a coulombic efficiency test, cycle life is 155-280 circles, fitting impedance is 21-33 ohm after ten circles of circulation, cycle life is long, the impedance is low, and good performance is obtained; and meanwhile, a relatively long service life of 660-1000 h can be obtained in a symmetrical battery test.

The invention discloses a preparation method of a composite solid electrolyte for inhibiting growth of lithium dendrites, which comprises the following steps of: heating a solid electrolyte in a plasma enhanced chemical vapor deposition device, introducing a mixed gas of nitrogen, hydrogen and methane to start a radio frequency plasma source, stopping introducing hydrogen and methane after closing radio frequency plasma, and cooling to room temperature to obtain the composite solid electrolyte for inhibiting growth of lithium dendrites. The method comprises the following steps: introducing nitrogen, cooling, taking out a sample, selecting a pure copper target, pre-sputtering to clean the surface of the target, mixing nitrogen and argon by adopting a direct current sputtering mode, preparing the sample and metal lithium into a symmetrical battery after the growth reaction is finished, and reacting the sample with Li < + > to generate Li3N and copper nanoparticles in the charging and discharging process, the copper nanoparticles which are well dispersed form a uniform electric field at an interface, and graphene is used as a three-dimensional structure interface of the substrate, has a high specific surface area and a porous structure, and can also effectively reduce the current density and relieve the volume effect, so that metal lithium is uniformly deposited, and the growth of lithium dendrites is effectively inhibited.

Solid electrolyte includes a first solid electrolyte that is a phosphate salt including Li and Ta, and a second solid electrolyte that is NASICON type solid electrolyte. In a cross section of the solid electrolyte, an area ratio of the first solid electrolyte is more than 10% and an area ratio of the second solid electrolyte is more than 10%.

The invention belongs to the technical field of battery electrolyte solutions, and specifically relates to an ultralow-temperature electrolyte solution as well as a preparation method thereof, a battery using the ultralow-temperature electrolyte solution and a preparation method thereof. The invention aims to provide the ultralow-temperature electrolyte solution as well as the preparation method thereof, the battery using the ultralow-temperature electrolyte solution and the preparation method thereof, which can perform large-multiplying-power charging and discharging under an ultralow-temperature environment. According to the technical scheme adopted by the invention, the ultralow-temperature electrolyte solution is obtained as follows: electrolyte salt is added into a solvent to obtain the electrolyte solution with mass concentration of 3-25 mol/kg, wherein the solvent is an aqueous solution with viscosity of 0-2.0 Pa.s, or a dielectric constant being greater than or equal to 30 C<2>/MM<2>; and the electrolyte salt is metal salt with solubility being greater than or equal to 3 mol/kg.

The invention belongs to the technical field of gold plating, and relates to a preparation technology of potassium aurous cyanide. The preparation technology comprises following steps: (1) washing a gold sheet: soaking a gold sheet in diluted nitric acid, washing the gold sheet by pure water, and drying; (2) carrying out electrochemical dissolution: carrying out electrolysis at a temperature of 65to 75 DEG C under a voltage of 6-7 V and a current density of 60-150 A/m2; (3) carrying out cooling and crystallization: carrying out twice cooling and crystallization on the electrolyte, filtering,washing obtained potassium aurous cyanide crystals by pure water until the pH reaches 8-10, and carrying out suction filtration in vacuum; and (4) drying: drying the crystals for 8 to 10 hours at a temperature of 80 to 100 DEG C. The provided preparation technology has the advantages that the electrolysis conditions are reasonable, a good environment is provided for gold electrolysis, the gold electrolytic rate is largely increased and can reach 85% or more; after crystallization, the gold mass percentage can reach 68.3% or more; the quality of prepared potassium aurous cyanide is stable; theproduction cost is controllable, and the economic benefit is good.