66results about How to "Lower electrochemical impedance" patented technology

The invention belonging to the technical field of lithium ion cells, and particularly relates to a method for improving hardness of a lithium ion cell by rapid formation. In the method, by adjusting the pre-baking time and temperature and the formation temperature of an electric core as well as the surface pressure on an electric core main body, the purpose of reducing the electric core polarization is achieved, high-current rapid formation is further realized, and finally the formation stopping potential is adjusted, so as to prepare the lithium ion cell with higher hardness. As compared with the prior art, the method has the following advantages: the high-temperature cramping and baking reshaping after formation is cancelled, so that the prepared electric core is higher in capacity; the electric core bears constant (or variable) pressure during the charge and discharge processes, thus the polarization in the charge and discharge processes is lower, and the capacity consistency of the prepared electric core is better; and because different temperatures and an SOC (state of charge) stopping manner are adopted for formation, the prepared electric core not only has excellent performance, but also has higher hardness.

The invention provides an all-solid-state lithium ion battery with low interface impedance and high compatibility. The battery comprises a composite positive pole piece and a composite negative pole piece, wherein the composite positive plate and the composite negative plate are a mixture of an active substance and solid electrolyte with a certain concentration gradient, the concentration gradientis that the concentration of the active substance is gradually reduced from a current collector to the outside, the solid electrolyte is gradually increased, and the outermost layer is only a solid electrolyte layer. In order to achieve interfacial compatibility of the positive and negative composite pole pieces, a surface of the outermost solid electrolyte layer of the composite pole piece is designed into a concave-convex groove, and the concave-convex surface is coated with low-melting polymer solid electrolyte; and lastly, the composite positive pole piece and the composite negative polepiece are tightly combined in a hot-pressing manner to assemble the battery. The battery can effectively solve a problem of compatibility between an electrode material and an electrolyte layer and a problem of large interface impedance of a solid-state battery, and thereby the cycling stability of the solid-state battery is improved.

The invention discloses a metal zinc negative electrode with a uniform mesoporous structure coating and a preparation method and application thereof, belonging to the technical field of aqueous zinc ion batteries. The metal zinc negative electrode comprises a zinc negative electrode and a clay slurry layer, and is prepared by pre-embedding zinc. The raw material powder of the clay slurry includes1-20wt% of polyvinylidene fluoride and 80-90wt% of clay material. The aqueous zinc ion battery negative electrode coating presented in the invention can play a role of a protective layer, isolate thedirect contact between the zinc negative electrode and the electrolyte to a certain extent, reduce the side reaction between the electrode and the electrolyte and improve the cycle stability. The layered porosity of the material itself can prevent dendrites from being generated and penetrating a diaphragm in the cycle process, alleviate the volume expansion of the negative electrode, reduce the occurrence of short circuit of the battery and improve the safety performance.

The invention relates to a preparation method for a NiCo2S4@NiCo2O4 nanoneedle composite catalytic electrode with a core-shell structure. The NiCo2S4@NiCo2O4 nanoneedle composite catalytic electrode grows in situ on the surface of nickel foil through two steps of the hydrothermal process. Compared with the prior art, the electrocatalytic electrode prepared through the method has the advantages that the electrical conductivity of a spinel oxide NiCo2O4 and the electrocatalytic water oxidation property are greatly improved through construction of the double-component core-shell structure, the advantages of being large in current density, high in electrocatalytic efficiency, stable in catalytic property and the like are achieved, only 290-mV overpotential needs to be supplied, the current density can reach 10 mA.cm<-2>, and the initial oxygen evolution potential is 0.46 V vs SCE. In addition, the electrode is simple in preparation method and low in preparation cost and has the potential application value in the energy and environment fields such as water decomposition hydrogen production and carbon dioxide reduction.

The invention provides a metal vanadate compound co-doped high-nickel ternary precursor and a preparation method thereof. A metal vanadate compound is doped in the coprecipitation reaction process, sothat one or two or more metals are synergistically doped to modify a nickel, cobalt and manganese or aluminum ternary precursor material; in the preparation process, a complexing agent solution and ametal solution are equally divided into an upper liquid inlet pipe and a lower liquid inlet pipe, and added into a reaction kettle; different regulation and control modes and growth process parameters are adopted in different stages of precursor growth; the ternary precursor with special primary particle morphology such as a flower sheet shape, a slender spindle shape, a thick and short rod shapeand the like or loose, porous, dense, hollow and other section morphology inside can be prepared, and the requirements of lithium batteries with different properties on precursors with different physical properties can be met.

The invention belongs to the technical field of preparation of cathode materials for lithium-ion batteries and specifically provides a double-layer coated cathode material LiNi0.6Co0.2Mn0.2O2 for a lithium-ion battery, wherein the coating amounts of Li3VO4 and PPy are 1 to 5 weight percent; Li3VO4 is a lithium fast ion conductor; by coating Li3VO 4, a protective layer can be provided and the lithium fast ion conductor also can be provided, so that ionic conductivity of the material is enhanced; in addition, lithium ions consumed during the formation of SEI and CEI films are made up and the cycle performance of the material is improved. The PPy is a fast electronic conductive material; by coating PPy, a second protective layer can be provided and the electronic conductivity of the materialcan be improved. Through double-layer coating of Li3VO4 and the PPy, the ionic conductivity is improved and the electrical conductivity is also improved; the cathode material is enabled to have super-high magnification discharge performance and higher discharge specific capacity; besides, double coating layers can more effectively inhibit the erosion effect of HF on the cathode material and enablethe cathode material to have excellent high voltage cycle stability.

The invention belongs to the field of electrochemistry and particularly relates to a high-capacity lithium-enriched positive electrode material and a reparation method thereof. The molecular formula of the high-capacity lithium-enriched positive electrode material is Li[Li<x-beta>Na<beta>Mn<1-y-z-alpha>Co<y>Ni<z>Y<alpha>]O2, wherein x is more than or equal to 0 and less than or equal to 0.6, y is more than 0 and less than or equal to 0.4, z is more than 0 and less than or equal to 0.4, alpha is more than or equal to 0 and less than or equal to 0.1 and beta is more than or equal to 0 and less than or equal to 0.2; the result of (1-y-z-alpha) is more than 0 and the result of (x-beta) is more than 0. The lithium-enriched positive electrode material containing Na and Y has the characteristics of low first-time irreversible capacity, large electrochemical capacity, high cycling stability, excellent rate performance and the like. The preparation method has the advantages that a preparation process is simple, raw materials are cheap and easily available, the cost is low, the high-temperature calcination time is very short, the repeatability is good and the industrialization is easy to realize.

The invention provides a solid-state battery and a preparation method thereof, and an electric vehicle. The solid-state battery comprises a positive electrode layer, a solid-state electrolyte layer located on the surface of the positive electrode layer and a negative electrode current collector located on the surface of the solid-state electrolyte layer, wherein the positive electrode layer comprises a positive electrode current collector and a positive electrode active material layer positioned on the surface of the positive electrode current collector, the positive electrode active materiallayer comprises positive electrode active particles and a first solid-state electrolyte, the first solid-state electrolyte is coated on the surfaces of the positive electrode active particles and/or filled among the positive electrode active particles in a completely molten and immediately quenched state, the solid-state electrolyte layer comprises a second solid-state electrolyte, the second solid-state electrolyte is clamped between the positive electrode layer and the negative electrode current collector in a state of complete melting and immediate quenching, and the density of the solid-state battery is 96-100%. According to the invention, the high density can greatly inhibit the short circuit problem caused by the growth of lithium dendrites, and the volume energy density and the charge-discharge cycle performance of the solid-state battery are obviously improved.

The invention discloses a positive electrode of a lithium ion battery. The positive electrode comprises a conductive substrate and positive paste, wherein the positive paste is coated on the conductive substrate and is formed by the mixing of a conductive agent, an active material and a binding agent, and the conductive agent is a three-dimensional conductive network formed by a zero-dimensional nanometer carbon substance with conductivity, a one-dimensional nanometer carbon substance with conductivity and a second-dimensional nanometer carbon substance with conductivity. In the positive electrode of the lithium ion battery, disclosed by the invention, three different-dimensional nano carbon conductive agents are adopted and mixed, on one hand, the nanoscale carbon conductive agents are beneficial for embedment and escapement of lithium ions, and on the other hand, conductive agents in three dimensions are mixed to form the three-dimensional conductive network, the difficulty of low conductivity of a pole plate brought by the conductive agents is overcome, the electrochemical impedance of the positive electrode is reduced, the conductivity of the pole plate is improved, and the electrochemical performance of the positive electrode is effectively improved.

The invention relates to a method for improving electrochemical performance through reducing graphene oxide (GO) by using a hydrogen (H2) and argon (Ar) mixed plasma. The method comprises the following steps of spin-coating GO on ITO (Indium Tin Oxide) conducting glass, drying, then, placing the ITO conducting glass into a plasma discharge chamber, wherein a graphite electrode is connected to the inside of the discharge chamber, and the electrode is connected with a radio-frequency alternating-current power supply capable of generating an inductive coupling plasma source; before discharging, introducing Ar, expelling air, then, starting a vacuum pump to vacuumize to about 2Pa, and introducing H2 and Ar mixed gas; when the total gas flow of H2 and Ar is 3sccm, and the flow ratio of H2 to Ar is 2 to 1, turning on the alternating-current power supply to generate a H2 and Ar mixed plasma, wherein the power of alternating current is 70w; directly acting the plasma flow on a GO film, and discharging for 5min to obtain a reduced graphene oxide (rGO) film. The method is not only capable of effectively reducing GO, but also is rapid, efficient, green and free of introducing impurities. The prepared rGO film is used as an electrode material, and the specific capacity of the rGO film is 211.8F/g which is higher than the specific capacity of rGO obtained by using other reducing methods.

The invention provides a platinum nano wire modified microelectrode array, and a platinum nano wire modification layer is arranged on the electrode surface of the microelectrode array. The microelectrode array takes platinum nano wires as surface modification layer, which is tightly bonded with the microelectrode substrate, and electrode failure due to disconnection can be prevented. The surface area of a modified microelectrode is greatly increased, electrochemistry impedance is greatly reduced, and the electrode charge injection capacity and charge storage capability are substantially increased. The power consumption of an implanted system can be reduced, and the electrical stimulation effect is improved. The modification layer has good biological compatibility, so that the application of the platinum nano wire modified microelectrode array in the biomedical field is increased. The invention further provides a preparation method of the platinum nano wire modified microelectrode array.

The invention relates to a method for rapidly preparing a flexible battery by using a carbon nanotube continuum. The carbon nanotube continuum is used for directly coating active substances, dispersion of carbon nanotubes is not needed, a traditional polymer binder and a traditional conductive agent are removed from the lithium ion battery electrode, meanwhile, a metal current collecto for supporting r is not needed, and the lithium ion battery prepared from the electrode has the characteristics of higher rate capability, high safety, high energy density, flexibility and the like. According tothe method, the active substances can be directly compounded, for example, a positive electrode can be selected from lithium cobalt oxide, lithium manganate, lithium iron phosphate, a ternary material and the like, and a negative electrode can be selected from graphite, lithium titanate, silicon carbon and the like; battery cells are stacked according to the sequence of the negative plate, the diaphragm and the positive plate, and then sleeved with an outer package, the edge is sealed after injection of an electrolyte, and manufacturing of the battery is completed. The method can be used forquickly and directly preparing the flexible battery electrode by using the carbon nanotube continuum. The problems that an existing lithium ion battery is not high in rate capability, low in energy density, dangerous and the like can be effectively solved, the manufacturing method is simple and rapid, and commercialized production of the lithium ion battery is facilitated.

The invention discloses an electrolyte of a high-voltage fast-charging lithium ion battery and the lithium battery. The electrolyte comprises a non-aqueous organic solvent, an electrolyte salt and anadditive, and the mass percentages of the non-aqueous organic solvent, the electrolyte salt and the additive in the electrolyte are 65%-90%, 10%-20% and 0-15% respectively. The electrolyte can improvethe normal-temperature quick charge cycle performance, the high-temperature storage performance and the low-temperature discharge performance of the high-voltage battery at the same time. The lithiumion battery prepared by adopting the electrolyte has lower surface density, is beneficial to reducing the impedance of the lithium ion battery, is smoother in lithium ion migration, can effectively improve the rate charge-discharge performance, and obviously improves the low-temperature discharge performance at the same time; the electrolyte of the high-voltage fast-charging lithium ion battery has the relatively high charging cut-off voltage, the capacity of the lithium ion battery can be improved by about 15%, and energy density reduction caused by surface density reduction is made up; andcompared with a conventional battery, the lithium ion battery has wider tabs, so that the ohmic impedance of the lithium ion battery is effectively reduced to facilitate electron transmission.

The invention provides an iron-nitrogen co-doped carbon and MXene compound as well as a preparation method and application thereof. The preparation method comprises the following steps: preparing an iron-doped imidazolinate framework; preparing Fe-N-C; mixing Fe-N-C and Ti3C2Tx, dispersing the mixture into N,N-dimethylformamide, and carrying out ultrasonic treatment; carrying out suction filtration, washing and drying, heating to 300 DEG C and 400 DEG C in a nitrogen atmosphere, and carrying out heat preservation for 0.5 hour to 2 hours so as to obtain the iron-nitrogen co-doped carbon and MXene compound FeNC@Ti3C2Tx. The iron-nitrogen co-doped carbon and MXene compound prepared by the preparation method can effectively catalyze an oxygen reduction reaction.

The invention provides a rat leg muscle electrical stimulation and electromyographic signal acquisition flexible device and a manufacturing method. The flexible device is provided with multiple independent finger electrodes. A certain gap exists between every two finger electrodes. Each finger electrode is provided with a plurality of stimulation electrodes at certain intervals, and a plurality of ground electrodes are distributed around each stimulation electrode and used for effectively controlling the current diffusion range and accurately controlling the electrical stimulation area. A plurality of recording electrodes are distributed on the central symmetry line of the whole flexible device, and reference electrodes are distributed near the recording electrodes. A micro-electrical stimulation interface and an electromyographic signal acquisition interface are integrated on the flexible device at the same time, micro-electrical stimulation can be exerted synchronously, and electromyographic signals at different positions are recorded. The functional electrical simulation and the electromyographic signal acquisition function are integrated, the optimized device structure and polymer material flexibility guarantee that shape preserving is good during attachment, and stimulation current and electrophysiologic signals are effectively transmitted.

The invention discloses a conductive polymer coated nickel-cobalt lithium aluminate cathode material and a preparation method thereof. The composite material is prepared by dissolving sodium dodecylbenzenesulfonate in deionized water, dispersing nickel-cobalt lithium aluminate powder in the solution, then adding a conductive polymer monomer and an oxidizing agent, and performing in situ polymerization on the surface of nickel-cobalt lithium aluminate at a low temperature to obtain the conductive polymer coated nickel-cobalt lithium aluminate cathode material. According to the invention, a conductive polymer with good electron transport performance is used to coat nickel-cobalt lithium aluminate, so as to effectively reduce the impedance between material particles, and improve the cycle performance of the material; at the same time, through polymer coating, the direct contact between electrolyte and an active material is reduced, and thus the structural stability of the material is improved.

The invention provides a vinylene carbonate modified binder and a lithium ion battery containing the vinylene carbonate modified binder. The vinylene carbonate modified binder comprises a matrix repeating unit A and a repeating unit represented by the following formula (1). According to the invention, an important film-forming aid vinylene carbonate in the electrolyte is introduced into the binder, the novel functionally modified bonding agent is prepared, when vinylene carbonate is introduced into a high-molecular chain of the existing binder, the adhesive property of the existing binder canbe improved, meanwhile, the modified binder is applied to an electrode plate, the lithium ion conduction capacity of the electrode plate is enhanced, the stability of the binder is also enhanced and the stripping force of the electrode plate is enhanced, and after the binder is applied to a lithium ion battery, the electrochemical impedance is reduced, the cycle performance of the battery is enhanced, and the low-temperature performance is better.

The invention discloses a corrosion inhibition treatment method for a magnesium alloy in a sodium chloride solution. The method comprises the following steps: sanding the magnesium alloy with waterproof abrasive paper, washing with water, carrying out oil removal at 70-80 DEG C in an alkaline oil removal solution, carrying out ultrasonic cleaning in 70-80-DEG C deionized water, washing with water, and blow-drying for later use, wherein the alkaline oil removal solution is composed of 30-50 g/L sodium phosphate, 10-20 g/L sodium silicate and 30-50 g/L sodium carbonate; preparing a 1-5 ml/L triethanolamine water solution, and magnetically stirring at 25 DEG C for 0.5 hour; and immersing the treated magnesium alloy in a triethanolamine water solution at 25 DEG C for 0.5-3 hours, taking out, washing with deionized water 2-3 times, and blow-drying, thereby completing the corrosion inhibition treatment of the magnesium alloy. The method is efficient and cheap, can well enhance the corrosion resistance of the magnesium alloy in the sodium chloride solution, and can not pollute the environment and equipment.

The invention discloses a preparation method and applications of a carburized titanium dioxide nanotube array, which belong to the technical field of lithium ion battery electrodes. The method disclosed by the invention comprises the following steps: in fluorine-containing electrolyte, by taking a pure titanium sheet as an anode, preparing an orderly titanium dioxide nanotube array by using an anodic oxidation method; carrying out low-temperature plasma carburizing treatment on the prepared nanotube array at low temperature, so that a carburized titanium dioxide nanotube array is obtained. By taking the prepared carburized titanium dioxide nanotube array as a lithium battery cathode material and assembling the array into a half cell, the cell is subjected to electrochemical performance detection, and detection results show that the reversible lithium insertion capacity of the cell is 235 mAh/g, which is far higher than an undoped sample capacity, and the cell has better cycling stability. The method has the advantages of simple operation, low cost, easiness for mass production, and the like, and has a broad application prospect in the fields of photocatalysis and lithium batteries, and the like.

The invention discloses a method for improving the electrochemical and dynamic properties of an La-Mg-Ni-based alloy electrode. The method comprises the steps of: smelting raw materials of La, Mg, Ni and Co into a cast alloy; crushing the cast alloy; and adding graphene and a graphene/nickel compound for mixing and ball-milling to prepare an La-Mg-Ni/graphene and La-Mg-Ni/graphene compound Ni-MH battery material. The method has the advantages that the electrochemical and dynamic properties of the material are obviously improved after the graphene and the graphene/nickel compound are added to La-Mg-Ni alloy powder for mixing and ball-milling; and a solid foundation is laid for later research of the Ni-MH battery material.

The invention relates to a thiourea (TU) additive for improving the nickel anode catalyst performance of a direct borohydride fuel cell .A preparation method of the additive comprises the following steps that at atmospheric pressure, on the condition that the temperature ranges from 293.15 K to 313.15 K, metal nickel is deposited on a Ni piece electrode through a constant electric potential (-0.8 V) method, and a prepared nickel-based catalyst serves as a nickel anode catalyst; a thiourea (TU) solution of 0.045 mol/L is prepared, 1 mL of the well-prepared thiourea solution is taken and diluted by five times to enable the concentration of the thiourea solution to be 0.009 mol/L, and the solution serves as an electrolyte additive .A hydrophobic thin film is formed on the surface of the nickel-based catalyst by means of thiourea (TU), the thin film changes distribution of BH4<-> on the surface of the nickel-based catalyst, and the BH4<-> electrochemical oxidation efficiency is improved .Shift of BH4<-> electrochemical oxidation peak potential is caused by addition of thiourea (TU), the electrochemical impedance of the system becomes smaller, the discharging efficiency becomes higher, the discharge potential is more negative, and the discharging time is longer.