32results about How to "High Li ion conductivity" patented technology

A positive electrode material for a nonaqueous lithium secondary battery and a lithium secondary battery that has superior cycle life and safety and reduced internal resistance of the battery at low temperature is provided. The positive electrode material for a nonaqueous lithium secondary battery comprise a layered structured complex oxide expressed by a composition formula Li_aMn_xNi_yCo_zM_αO₂, where 0<a≦1.2, 0.1≦x≦0.9, 0≦y≦0.44, 0.1≦z≦0.6, 0.01≦α≦0.1, and x+y+z+α=1. A diffraction peak intensity ratio between the (003) plane and the (104) plane (I(003)/I(104)) in an X-ray powder diffractometry using a Cu—Kα line in the X-ray source is not less than 1.0 and not more than 1.5.

A solid electrolyte material represented by Formula 1:

L_1+2x(M1)_1-x(M2)(M3)₄  Formula 1

• • wherein 0.25<x<1, L is at least one element selected from a Group 1 element, M1 is at least one element selected from a Group 2 element, a Group 3 element, a Group 12 element, and a Group 13 element, M2 is at least one element selected from a Group 5 element, a Group 14 element, and a Group 15 element, and M3 is at least one element selected from a Group 16 element, and wherein the solid electrolyte material has an I-4 crystal structure.

The invention discloses a lithium-sulfur battery composite cathode material, a preparation method thereof and a lithium-sulfur battery. The composite cathode material is formed by compositing raw materials comprising an elemental sulfur, metal-nonmetal element co-doped conductive graphitized carbon material and a lithium-conducting polymer; during the preparation process, the metal-nonmetal co-doped conductive graphitized carbon material, the lithium-conducting polymer and the solution with the elemental sulfur are stirred and mixed, then the solvent is volatilized, and heat-treated, thereby obtaining the composite cathode material having high conductivity and capable of improving the utilization rate of an active substance sulfur. The preparation method is simple, the process conditions are mild, the production cost of the lithium-sulfur battery cathode material is greatly reduced, and industrial production requirements are met; the lithium-sulfur battery made of the composite cathodematerial has a high discharge specific capacity, a stable cycle performance and a high safety performance, without the need for a current collector, and without need to add a conductive agent and a binder.

The invention provides sulfide electrolyte materials shown by a formula (I) and sulfide electrolyte materials shown by a formula (II). The invention further provides a design thought and a preparation method of the sulfide electrolyte materials. A certain amount of lithium phosphate is doped and added to or compounded to sulfide solid electrolytes, and the ionic conductivity of the sulfide electrolyte materials is improved.

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.

The invention belongs to the field of lithium ion solid electrolyte, and particularly discloses novel lithium ion conduction oxide solid electrolyte and a method for preparing the same. The method particularly includes weighing raw materials according to designed stoichiometric ratios and mixing the raw materials with one another by means of ball-milling by the aid of wet processes; carrying out step-by-step calcination on the mixed raw materials to prepare solid electrolyte powder; maintaining pressures for the solid electrolyte powder under appropriate pressure conditions for 30-60 min, thenburying blanks in powder with identical components, heating the blanks at the speeds of 1-2 DEG C/min until the temperatures of the blanks reach 1100-1200 DEG C and preserving heat for 12-24 h to obtain the required novel lithium ion conduction oxide solid electrolyte. The novel lithium ion conduction oxide solid electrolyte and the method have the advantages that technological processes are simple, and the novel lithium ion conduction oxide solid electrolyte and the method are low in cost; the novel lithium ion conduction oxide solid electrolyte prepared by the aid of the method is high in lithium ion conductivity and excellent in chemical stability and can be used as solid electrolyte for lithium ion batteries.

An electrode material is composed of an electrode active material represented by the general formula LiMPO₄, where M=[Fe_tMn_1-t], and t is a number between 0 inclusive and 1 inclusive. Each of the primary particles of the electrode active material has a layer on its surface, said layer having a Li ion conductive substance including Li, one or both of Fe and Mn, P and O, and conductive carbon C. Minute secondary particles are formed from a plurality of the primary particles that aggregate, and bind to each other via the layer comprising the Li ion conductive substance and the conductive carbon C. The electrode material has an area-equivalent diameter of 45 nm or more determined by a specific surface area obtained from the nitrogen adsorption Brunauer, Emmett and Teller (BET) multipoint method.

A positive electrode material for a lithium secondary battery, including: a positive electrode active material represented by Li_1+αNi_xCo_yMn_zM^I_tO₂ and having a layered rock salt-type crystal structure; an electron-conducting oxide represented by La_pAe_1−pCo_qM^II_1−qO_3−δ; and a Li ion-conducting oxide including Li element, 0 element, and at least one element selected from W, P, Nb, and Si.

The invention discloses a lithium sulfide series solid electrolyte material added with lithium silicon alloy powder and a preparation method thereof. The preparation method comprises the following steps that (1) under the atmosphere protection condition, lithium sulfide, phosphorus sulfide, the lithium silicon alloy powder and sulfur are weighed according to a mole ratio of (2.5 to 3.5) to (0.5 to 1.0) to (0.05 to 0.20) to (0.01 to 0.1); the materials are uniformly mixed to obtain an amorphous state lithium sulfur phosphorus and silicon mixture; (2) the amorphous state lithium sulfur phosphorus and silicon mixture is sealed under the atmosphere protection condition; then, the temperature is raised to 100 to 250 DEG C under the vacuum condition; heat treatment is performed; the lithium sulfide series solid electrolyte material is obtained. The concentration of migratable lithium irons in the lithium sulfide series solid electrolyte is improved through adding the high-lithium-content lithium silicon alloy powder capable of easily forming the amorphous state, so that the lithium ion conductivity of the obtained solid electrolyte material is improved.

The invention provides an electrode plate, a secondary battery comprising the electrode plate and a device. The electrode plate comprises a current collector, and the functional surface of the current collector comprises a tab region and an active layer region located on the periphery of the tab region; the active layer region comprises a first active layer region and a second active layer region which are adjacent, and the first active layer region is close to the tab region; the first active layer area is provided with a first active layer, the second active layer area is provided with a second active layer, and the thickness of the first active layer is smaller than that of the second active layer; the compaction density Q1 of the first active layer and the compaction density Q2 of the second active layer meet the condition that Q1/Q2 = (0.6-1): 1. The electrode plate has relatively low impedance, and meanwhile, the secondary battery comprising the electrode plate can have good cycle performance.

The invention provides a composite electrode material and a preparation method and application thereof.The composite electrode material comprises a pole piece base body and an artificial solid electrolyte layer wrapping the surface of the pole piece base body, the artificial solid electrolyte layer is composed of a first polymer, and the structure of the first polymer is shown in the formula I; wherein n is equal to 10 to 1000; the pole piece substrate is at least one of lithium metal or a composite material containing metal lithium. According to the invention, the ether-containing side group copolymer is used as the artificial solid electrolyte layer to coat the surface of the electrode substrate to protect the electrode substrate, the solid electrolyte layer interface has high ion conduction rate and strong lithium affinity, the electrolyte is prevented from reacting with the electrode substrate while inducing uniform deposition of lithium ions, the interface of the electrode substrate is stabilized, and the service life of the electrode substrate is prolonged. And therefore, the consumption of the electrolyte is reduced.

The invention provides an electrolyte for a lithium ion battery. The electrolyte comprises a solvent, an electrolyte salt and an additive, wherein the solvent contains ethylene carbonate. The used solvent is more beneficial to lithium salt dissociation and has higher lithium ion conductivity, and the adopted additive forms a solid electrolyte membrane which has lower electrode interface impedance, so that higher ion conduction capability can be realized, the shortages of the electrochemical reaction process during high-power discharge are overcome, and the battery using the electrolyte provided by the invention has higher power performance.

The invention provides an electrolyte as well as a preparation method and application thereof. The electrolyte comprises a lithium salt, an additive and an organic solvent; the additive comprises a sultone compound with a structure as shown in a formula I. According to the electrolyte, components are designed, particularly, the sultone compound with a specific structure is adopted as the additive, so that a dense, stable and elastic SEI film is formed in the charging and discharging process of a battery, the lithium ion conductivity of the SEI film is improved, the impedance can be effectively reduced, side reactions are reduced; and the consumption and degradation of the electrolyte in the use process are reduced, so that the internal resistance of the battery is reduced, the capacity retention ratio of the battery is high, the normal-temperature and high-temperature cycle performance of the battery is remarkably improved, and the service life of the battery is prolonged.

The invention discloses a double-chain polyethylene oxide modified covalent organic framework as well as a preparation method and application thereof. The covalent organic framework is prepared by taking PEG-n, n-NHNH2 (n = 1, 2, 3, 6) and 1, 3, 5-tris (4-formylphenyl) benzene as raw materials, mesitylene and 1, 4 dioxane as solvents and acetic acid as a catalyst through a solvothermal method. The covalent organic framework provided by the invention has good crystallinity and thermal stability, and shows good lithium ion conduction performance and solid-state lithium battery cycle performance at high temperature.

The invention discloses a lithium ion conductor material with a porous and non-porous composite structure, and belongs to the field of preparation of solid electrolyte materials of solid lithium ion batteries. The material is realized by doping non-porous solid lithium ion conductor material powder; The non-porous solid-state lithium ion conductor powder is selected from Li1.3Al0.3Ti1.7(PO4)3(LATP) and Li0.33La0.56TiO3(LLTO); the doping amount of the LATP is 0 wt%-20 wt%, and the doping amount of the LLTO is 0 wt%-25 wt%. The lithium ion conductor powder added into the lithium ion conductor material is one of LLTO and LATP. Compared with an undoped perovskite type lithium ion conductor material, the composite lithium ion conductor material prepared by the invention has the advantages that the total conductivity is obviously improved, the lithium ion transference number of the lithium ion conductor material is close to 1, and the composite lithium ion conductor material has high lithium ion conduction performance.

The invention discloses a SiO<2> coated Co<2+>-Cu<2+> doped amorphous nickel nitrate lithium battery negative electrode material. The preparation process is as follows: coating SiO<2> on Co<2+>-Cu<2+> doped amorphous nickel nitrate particles in combination with a micro-emulsion and a spray-drying method, thereby resisting the erosion of an electrolyte; and then, under a high vacuum condition, removing crystallization water in a system by adopting a special heat treatment step to form the SiO<2> coated Co<2+>-Cu<2+> doped amorphous nickel nitrate lithium battery negative electrode material. As Co<2+> is doped in the system, the electronic conductivity of the system is improved; with Cu<2+> ions, a Ni-O space structure is enabled to produce distortion and a lithium ion diffusion-migration channel is expanded so that the electric conductivity of lithium ions is improved; the particularly beneficial effect is that the material is amorphous and is isotropic, thereby being conductive to rapid conduction of the lithium ions; and thus, the overall electrochemical performance of nickel nitrate is greatly improved.

The invention discloses a gel electrolyte of a lithium ion battery and a preparation method of the gel electrolyte. The gel electrolyte comprises a solvent, an additive, lithium salt and an organic polymer-nanoparticle combination agent, wherein organic polymers and nanoparticles in the combination agent are combined by forming a new covalent bond. Compared with the prior art, the lithium ion battery with the gel electrolyte has the advantages that the problems of difficulty in uniform dispersion, easiness in settlement and viscosity increase caused by direct addition of the nanoparticles into an existing gel electrolyte are solved; the organic polymer-nanoparticle combination agent is clear and transparent, and low in viscosity; the lithium ion conduction performance of the gel electrolyte can be improved, and the heat stability, oxidation resistance and all mechanical performances of a cell can be improved; the prepared lithium ion battery is high in capacity and ideal in safety performance.

The present invention provides a positive electrode material for lithium secondary batteries, having: a positive electrode active material containing Li; and a cover disposed on the positive electrode active material, and containing Li and F, and further containing one or two or more cover elements from among Al, Ti, Zr, Ta and Nb. With a Point a as an arbitrary point of the cover in contact with the positive electrode active material, a Point c as a point on the surface of the cover at a shortest distance from the Point a, and a Point b as a midpoint between the Point a and the Point c, an analysis of the Point a, the Point b and the Point c by X-ray photoelectron spectroscopy yields a ratio of Li concentration at the Point a with respect to the Li concentration at the Point b is 1.1 or higher and lower than 10.8, and a ratio of F concentration at the Point c with respect to F concentration at the Point b is 1.1 or higher and lower than 51.1.