6results about How to "Does not affect electrochemical performance" patented technology

The invention belongs to the technical field of electrolyte additives, and particularly relates to an estersil compound and a preparation method and application thereof. Wherein the general formula of the estersil compound is as shown in formula (I) to formula (IV), R1 is methyl, ethyl, isopropyl, vinyl or phenyl, and R2 is CH2 = CH <->, CH3 <->, CH3CH2 <->, (CH3) 2CH <->, (CH3) 3C <-> or H <->. The estersil compound provided by the invention can be used as an electrolyte additive, and can inhibit discoloration of an electrolyte in an electrochemical device, so that the storage time is prolonged, and the comprehensive performance of the electrochemical device is improved.

This invention discloses a high-strength, heat-resistant lithium-ion battery separator and its preparation method, belonging to the field of lithium-ion battery technology. The separator is a multilayer composite structure, comprising: a rigid porous framework membrane prepared from a rigid polymer material via thermally induced phase separation as a support layer; and a functional layer composited on the surface of the support layer. The functional layer is a gel electrolyte separator formed from a covalent organic framework material via electrospinning, containing a hierarchical porous network of micropores, mesopores, and macropores, and a flame retardant dispersed in the pores of the separator. The preparation method includes: thermally induced phase separation after melt blending, biaxial stretching and extraction, electrospinning surface deposition, flame retardant introduction, and hot pressing. The separator of this invention, through the synergistic effect of the rigid framework and the COFs gel layer, possesses high mechanical strength, high heat resistance, high ionic conductivity, and thermal runaway management functions, effectively improving the safety and cycle stability of semi-solid-state lithium-ion batteries.

This invention relates to the field of lithium-ion battery technology, and discloses a composition for preparing a fire-retardant composite electrolyte, the fire-retardant composite electrolyte, and a method for preparing the same. The composition contains the following components: lithium hexafluorophosphate, solvent, flame retardant, overcharge protection agent, surface film-forming agent, cathodic protection agent, and fluorocarbon surfactant; the flame retardant is selected from at least one of nitrogen-containing compounds and organophosphorus compounds; the overcharge protection agent is selected from at least one of tris(4-methoxyphenyl)phosphine and 2,5-di-tert-butyl-1,4-dimethoxybenzene. The fire-retardant composite electrolyte prepared from the composition provided by this invention can improve battery safety while ensuring high electrochemical performance when used in lithium batteries.

The invention provides a current collector, a positive pole piece, an electrochemical device and electronic equipment, the current collector comprises a polymer layer and a conductive metal layer covering at least one side surface of the polymer layer, and the ratio of the mass percentage content of a carbon element to the mass percentage content of a conductive metal element in the current collector is 0.1-5. The current collector is formed by stacking a polymer layer and a conductive metal layer, the conductive metal layer enables the current collector to have a current collecting effect, and the polymer layer has good strength, ductility and insulativity, plays a buffering role in extrusion and collision, and reduces deformation, so that the internal resistance change rate of an electrochemical device made of the current collector is reduced; and when short circuit occurs, the resistance of the current collector is increased to be almost insulated, so that the safety and the stability of the electrochemical device are improved. The ratio of the mass percentage content of the carbon element to the mass percentage content of the conductive metal element in the current collector per unit area is set to be 0.1-5, so that the current collector can give consideration to good conductivity, strength, safety and stability.

This invention belongs to the field of lithium-ion battery technology, specifically relating to a Ni-doped molybdenum carbide / lithium oxalate composite lithium replenisher. The invention first obtains a Ni molecular catalyst through a liquid-phase reaction of triethanolamine and nickel chloride in ethanol, followed by calcination with Mo₂C to form a composite Ni-doped molybdenum carbide catalyst. Then, using an anti-solvent crystallization method, the lithium replenisher solution is dropwise into an organic solvent containing the catalyst, stirred, and then vacuum dried. The lithium replenisher particles adhere to the catalyst surface and / or pores, forming the composite lithium replenisher. This composite lithium replenisher, by combining lithium oxalate with the Ni-doped molybdenum carbide catalyst, utilizes the highly active catalytic sites, excellent electronic conductivity, and synergistic catalytic effect of Ni-doped molybdenum carbide to reduce the decomposition voltage of lithium oxalate, improve its conductivity and decomposition rate, thereby significantly improving the battery's initial efficiency, capacity, and cycle performance. Furthermore, the preparation process is simple, highly compatible, and has good commercial application prospects.

The invention provides a positive pole piece with an anisotropic heat-conducting network structure, a preparation method of the positive pole piece and a lithium ion battery. The positive pole piece comprises a positive current collector and a positive active material layer arranged on the surface of the positive current collector, the positive active material layer comprises a positive active material, a binder and a conductive agent, and the positive pole piece also comprises heat conduction materials which are orderly arranged along the thickness direction of the positive pole piece and are coated with magnetic materials on the surfaces, the heat conduction material is selected from a two-dimensional sheet material and / or a one-dimensional tubular material, the included angle between the plane direction of the two-dimensional sheet material or the axial direction of the one-dimensional tubular material and the plane direction of the positive electrode current collector is 70-110 degrees, and the ratio of the heat conductivity coefficient Kz in the thickness direction of the positive electrode plate to the heat conductivity coefficient Kx in the plane direction of the positive electrode plate meets the condition that Kz / Kx is larger than or equal to 5. The positive pole piece provided by the invention can effectively control directional transmission of heat in the lithium ion battery, reduce temperature rise caused by fast charging and prolong the service life of the lithium ion battery.