31results about How to "Improve high voltage performance" patented technology

The invention belongs to the technical field of lithium-ion batteries, and discloses a lithium-ion battery electrolyte and a lithium ion battery with the same. The lithium-ion battery electrolyte is prepared from an organic solvent, conductive lithium salt and an additive; the additive is prepared from a common additive and a phosphoric acid ester additive, and the phosphoric acid ester additive has the structural formula shown in the formula (I) (please see the specification). According to the lithium-ion battery electrolyte, the phosphoric acid ester additive is added, the interface characteristics of the electrode/electrolyte of the lithium-ion battery can be improved, the stability is improved, interface impedance is reduced, the cycling stability, the high-temperature performance and the high-voltage performance of the lithium ion battery are improved accordingly, gas generation caused by organic solvent decomposition is inhibited, and expansion of the battery is reduced.

The invention relates to a positive electrode material of a high-capacity dynamic-type nickel-rich lithium ion battery and a preparation method. The molecular formula of the positive electrode material of the high-capacity dynamic-type nickel-rich lithium ion battery is LiaNi1-x(MM')xO2.M''O, wherein a is equal to 0.9-1.2, x is more than or equal to 0 and less than or equal to 0.7, and M is at least one of Co, Mn and Al; M' is at least one of Co, Al, V, Mn, Zr, Mg, Ti, Cr, Zr, La, Ce, Pr, Nd, Nb, Mo, Y, Sr, Ba, B, Sr, Sn and Ta; M''O is a cladding layer, and M'' is Co and Al. The invention also relates to a preparation method for the positive electrode material of the high-capacity dynamic-type nickel-rich lithium ion battery. The material machining performance is excellent, the battery prepared by utilizing the material, the cycling performance and the high-voltage performance are excellent, the safety and stability in use can be realized, not only can the application performance requirement of a portable electronic device on the battery be met, but also the positive electrode material is applicable to the power battery.

The invention discloses high-voltage lithium ion battery electrolyte, a preparation method and application of electrolyte. The high-voltage lithium ion battery electrolyte comprises an organic solvent, conductive lithium salt and a functional additive, wherein the organic solvent is prepared from a cyclic carbonate solvent, a fluoro solvent and a linear carbonic ester solvent, the content of the fluoro solvent in the high-voltage lithium ion battery electrolyte is 0.1-40wt.%, the content of the functional additive is 0.01-5wt.%, and the concentration of the conductive lithium salt in the organic solvent is 0.8-1.5mol/L. According to the high-voltage lithium ion battery electrolyte, the interfacial property of the anode and the cathode of the battery and the electrolyte can be improved, and the stability of the electrolyte can be improved, so that the cycle life of the high-voltage lithium ion battery is prolonged, the high-temperature property of the high-voltage lithium ion battery is improved and the working voltage of the high-voltage lithium ion battery is increased to be above 4.5V.

The invention discloses a gradient type monocrystal-like positive electrode material and a preparation method thereof. The general chemical formula of the gradient type monocrystal-like positive electrode material is LiNixCoyMn (1-x-y) AnO2, wherein 0.5<=x<=0. 8, 0.1<=y<=0.2, 0<=n<=0. 3. The gradient type ternary precursor NixCoyMn (1-x-y) (OH)2 is prepared by the method. The change of the concentration of the added nickel salt solution, the cobalt salt solution and the manganese salt solution is controlled to gradually reduce the nickel content and gradually increase the cobalt and manganesecontent in the components from the core to the surface of the precursor, and the particle size of the precursor is controlled to be 2-5um. The step-by-step sintering mode is used and beneficial to theindustrial production and can reduce the inconsistency of the obtained product. Finally, the obtained gradient type monocrystal-like lithium nickel cobalt manganate positive electrode material has good discharge performance and cycle performance at the high voltage of 4.5V.

The invention provides a positive electrode material, and a preparation method thereof and a lithium ion battery. The positive electrode material comprises a substrate and a coating layer coating the substrate, the substrate is a high-nickel ternary material, and the coating layer is a composite oxide coating layer containing Al, Co and Mn. The preparation method comprises the following steps: 1) mixing a matrix precursor with a lithium source, and calcining to obtain a matrix material; (2) mixing an aluminum source, a cobalt source and a manganese source in a dissolving agent, adding a coprecipitator, standing for reaction, and then carrying out solid-liquid separation to obtain a coating material; and 3) mixing the base material and the coating material, and performing heat treatment to obtain the positive electrode material. The positive electrode material provided by the invention can well solve the safety problem and the cycle stability problem of a high-nickel ternary material, reduces the residual alkali amount on the surface of the positive electrode material, and has the advantages of low residual alkali, low mixing degree, high conductivity, high capacity, high cycle efficiency and the like.

The invention discloses high voltage electrolyte containing a benzonitrile additive, and a preparation method of the high voltage electrolyte. The high voltage electrolyte is prepared from the following raw materials in parts by mass: 1 part of cyclic carbonate, 1 part of linear carbonate diethyl carbonate, 1 part of ethyl methyl carbonate, 1 part of inorganic conductive lithium salt and 1 part ofadditive benzonitrile. The high voltage performance can be improved by adding the benzonitrile additive, a dense and uniform low-impedance protective film can be formed on the surface of a positive electrode material during battery cycling, and the protective film can inhibit the oxidative decomposition of the electrolyte solvent and can maintain the structural stability of the positive electrodematerial. The high voltage electrolyte is reliable in effect; the high-voltage functional additive benzonitrile is added into the electrolyte, so that the stability of a lithium ion battery is improved under high voltage; the method is simple, the operation is simple, the addition amount is small, and the high voltage electrolyte is practical and economical.

The invention provides an electrolyte for a high-voltage lithium ion battery as well as a preparation method and application of the electrolyte. The electrolyte can improve the high-voltage performance of the lithium ion battery. The high-voltage electrolyte for the lithium ion battery comprises a non-aqueous organic solvent, a lithium salt and an electrolyte additive, the electrolyte additive comprises a disulfuryl compound, lithium difluorophosphate and tris (trimethylsilyl) phosphate, the bis-sulfonyl compound can form a stable SEI film on the surface of a positive electrode, the lithium difluorophosphate can improve the Li < + > conductivity of the SEI film, and the tris (trimethylsilyl) phosphate has the higher electrochemical stability, so that the oxygenolysis of the electrolyte onthe surface of an electrode is prevented. Through the synergistic effect among the bis-sulfonyl compound, the lithium difluorophosphate and the tri (trimethylsilyl) phosphate, the prepared electrolyteis more stable in property under a high voltage, and the battery shows better cycle performance under the high voltage.

The invention discloses a non-aqueous electrolyte, a preparing method of the non-aqueous electrolyte and a lithium secondary battery. The non-aqueous electrolyte mainly comprises an organic solvent, conductive lithium salt and an additive. The organic solvent is composed of cyclic carbonate and a linear carbonic ester solvent. The concentration of the conductive lithium salt in the organic solvent is 0.8-1.5 mol/L, the additive is one or more of compounds, of which the dosage is 0.01-8.0 percent by weight, shown in the following general formula (1), and the formula can be seen in the specifications. The compounds are added into the non-aqueous electrolyte so that the service life of a lithium ion battery can be prolonged, the high voltage (larger than 4.2 V) can be improved, the high and low temperature performance can be enhanced, and the air expansion problem of the battery can be solved.

The invention belongs to the field of preparation of ceramic materials, and particularly relates to calcium zirconate and tantalum doped potassium sodium niobate-based piezoelectric ceramic and a preparation method and application thereof. The high piezoelectric property of the KNN-based piezoelectric ceramic can be greatly improved through the CaZrO3-doped potassium sodium niobate-based ceramic,and the d33 of the CaZrO3-doped KNN-based ceramic at 160 DEG C is greater than or equal to 200Pc/N. Meanwhile, tantalum ions are doped into the CaZrO3-KNN-based ceramic so that the CaZrO3-KNN-based ceramic still keeps good piezoelectric property and temperature stability under the condition that high-density lead-free ceramic is obtained.

The invention relates to the technical field of ternary lithium ion secondary batteries, and particularly discloses a ternary lithium ion battery electrolyte which comprises a functional additive, a solvent and inorganic conductive lithium salt, wherein the functional additive. The invention further discloses an application of the electrolyte containing the functional additive. In the invention, the functional additive is added into the electrolyte. Serving as a film-forming additive, the functional additive can form a layer of uniform and compact coating film on the surface of the positive electrode of the lithium ion battery, so that the oxidative decomposition of an electrolyte solvent and the corrosion of an electrolyte and lithium salt decomposition product HF to an electrode materialare inhibited, the structure of the positive electrode material is stabilized, the dissolution of transition metal ions is inhibited, and the cycling stability and the rate performance of the lithiumion battery at high voltage and high temperature are improved.

The invention relates to the field of lithium ion batteries, in particular to a composition for preparing a solid polymer electrolyte and application thereof. The composition comprises a nonflammable electrolyte and a monomer containing unsaturated double bonds, wherein the mass percentage content of the monomer containing the unsaturated double bonds in the composition is 1-50%. The composition provided by the invention has high thermal stability and high voltage resistance, and can be used for preparing a solid polymer electrolyte and a lithium ion battery which has the characteristics of high voltage, high safety, difficulty in volatilization, difficulty in inflation, nonflammability and the like. Besides, the composition has the advantages of high flash point, high boiling point, high voltage resistance, low viscosity and the like, and the safety of the soft package battery can be remarkably improved; and the polymer electrolyte is further prepared by adopting an in-situ curing technology, so that the safety of the high-voltage soft package lithium ion battery is doubly guaranteed.

The invention provides an electrolyte for a high-voltage lithium ion battery as well as a preparation method and application of the electrolyte. The electrolyte can improve the high-voltage performance of the lithium ion battery. The high-voltage electrolyte for the lithium ion battery comprises a non-aqueous organic solvent, a lithium salt and an electrolyte additive, and the electrolyte additivecomprises a bis (sulfonyl) compound, lithium bis (trifluoromethanesulfonyl) imide and fluoroether, wherein the dosage of the bis-sulfonyl compound is 0.1 wt%-5wt% of the total weight of the electrolyte, the dosage of the lithium bis (trifluoromethanesulfonyl) imide is 0.1 wt%-2wt% of the total weight of the electrolyte, and the dosage of the fluoroether is 0.5 wt%-10wt% of the total weight of theelectrolyte. The lithium ion battery electrolyte can effectively improve the cycle performance of the lithium ion battery in a high-voltage environment, and the internal resistance change of the battery is small.

The invention discloses an electrolyte additive containing thiazolyl, amino and cyano, an electrolyte additive containing the additive and a lithium ion battery. The structure of the electrolyte additive is as shown in a structural formula I in the specification. The additive contains three effective groups, namely an imidazolyl group, an amino group and a nitrile group. Both thiazolyl and amino have alkalescence, so that HF in the electrolyte can be effectively reduced, precipitation of transition metal ions in the positive electrode of the lithium ion battery is reduced, and the stability of the positive electrode and an electrolyte interfacial film is enhanced; the cyano group can be complexed with transition metal of the positive electrode of the lithium ion battery to form a film on the surface of the positive electrode, and the interfacial film can effectively inhibit decomposition of electrolyte and reduce precipitation of transition metal ions. Therefore, the battery system containing the additive has better high voltage resistance, normal temperature and high temperature cycle performance and high temperature storage performance.

The invention provides an electrolyte, a preparation method and application of the electrolyte, a lithium ion battery and application of the lithium ion battery, and belongs to the technical field ofelectrolytes. The electrolyte provided by the invention is prepared from an additive, inorganic conductive lithium salt and a solvent, wherein the additive is fluorine-containing phosphate, and the chemical formula of the fluorine-containing phosphate is M1xM21-0.5xPO3F and/or M1PO2F2. The electrolyte containing the fluorine-containing phosphate is used in the lithium ion battery, the electrochemical activity of the surface of a positive electrode material can be reduced in a circulation process, oxidative decomposition of the solvent of the electrolyte is inhibited, the structure of the positive electrode material is stabilized, and the cycling stability and the rate performance of the lithium ion battery under high voltage are improved.

The invention discloses a preparation method of a lithium iron phosphate/graphene oxide/platinum composite electrode material and belongs to the field of electrode materials. Graphene oxide is firstly dispersed in the mixed acid of concentrated sulfuric acids for treatment, the treated graphene oxide is dispersed in platinum chloride and is irradiated by using an ultraviolet lamp, filter residues obtained through separation is dispersed in deionized water, is irradiated by using the ultraviolet lamp and then is dried to obtain graphene oxide supported platinum particles, a hydrothermal method is utilized to prepare lithium iron phosphate particles, then the lithium iron phosphate particles are dispersed in water, the graphene oxide supported platinum particles are added to dispersion liquid, stirring, mixing and drying are performed, the dried product is subjected to high-temperature treatment, and then the composite material is obtained. The reaction conditions are mild, the operating process and a process are simple, a generated conductive composite layer can obviously improve the rate capability, the prepared composite material can obviously improve the rate capability of batteries, the high voltage performance is good, the product purity is high, and the cost is lower.

The invention discloses an electrolyte additive for improving the high-temperature performance of a lithium battery, an electrolyte and an electrochemical device. The electrolyte additive comprises at least one selected from a compound I or a compound II with a structure shown in the description, and the electrolyte additive can relatively improve the capacity retention ratio of a lithium battery containing the electrolyte additive at high temperature, and also can improve the capacity retention ratio at relatively high temperature and charge-discharge voltage.