12results about How to "Guaranteed rate performance" patented technology

The utility model discloses an electrode plate and a lithium ion battery. The electrode plate comprises a current collector, a positive electrode and a negative electrode, the edges of the two sides of the current collector are coated with the functional coatings; the active material coating is coated on at least one surface of the current collector and covers the functional coating; the ratio of the thickness of the functional coating to the thickness of the current collector is 0.2-1, and the functional coating is used for weakening lithium ion transmission. According to the invention, the balance between the conductivity of the coating and the lithium removal capacity of the active substance is maintained by adjusting the parameters of the coating, that is, the lithium ion de-intercalation speed is controlled by optimizing the structure and parameters of the pole piece coating, so that the capacity of improving the charging rate of the battery cell is achieved.

The invention provides a double-layer double-high type electrode, a reserve lithium battery and a preparation method thereof, the double-layer double-high type electrode comprises a current collector, a first active layer and a second active layer, the first active layer is located between the current collector and the second active layer, the first active layer contains an energy type active material, and the second active layer contains an energy type active material. The second active layer contains a pre-charged power type active material, and the open-circuit voltage difference between the energy type active material and the pre-charged power type active material is less than or equal to 0.5 V. The invention provides the double-layer double-high type electrode for the reserve lithium battery, which is quick in activation, high in energy density and good in rate capability, an efficient conductive network is constructed, and the discharge performance of the battery is improved; the porosity of the second material layer is regulated to be greater than that of the first material layer, and the seepage flow guide grooves are dug in the surface of the second material layer, so that the electrolyte infiltration rate of the electrode is improved, and the activation time is shortened.

The invention relates to the field of sodium ion batteries, and discloses a sodium vanadium phosphate composite positive electrode active material, a preparation method thereof and a sodium ion battery. The sodium vanadium phosphate composite positive electrode active material comprises a sodium vanadium phosphate inner core and a carbon coating layer coating at least part of the surface of the sodium vanadium phosphate inner core; and the compaction density of the sodium vanadium phosphate composite positive active material is greater than 1.8 g / cm < 3 >. When the positive electrode active material with relatively high compaction density is applied to the sodium ion battery, the diffusion path of sodium ions can be reduced, the energy density of the battery is improved, the discharge capacity of the battery is increased, the internal resistance of the battery is reduced, the polarization loss is reduced, the voltage platform of the battery is improved, and the rate capability and the cycle performance of the battery are ensured.

The present application provides a negative electrode sheet for a secondary battery and a preparation method thereof, as well as a secondary battery, a battery module, a battery pack and an electric device comprising the negative electrode sheet. The negative electrode sheet of the present application includes a current collector and an active material layer coated on at least one surface of the current collector, the active material layer includes a first graphite layer, a lithium titanate layer and a second graphite layer, the first graphite layer is arranged on at least one surface of the current collector, the lithium titanate layer is arranged on the surface of the first graphite layer, the second graphite layer is arranged on the surface of the lithium titanate layer, and the OI value of the first graphite layer is greater than or equal to 20.0, and the OI value of the second graphite layer is less than or equal to 15.0.

The invention discloses a gel-resistant positive electrode slurry and porous electrode preparation. The positive electrode slurry in the invention gels slowly, and the surface and the inside of the electrode after drying have pores, which are helpful to increase the electrode liquid retention, improve the rate performance of the battery core, and reduce the polarization of the electrode. The invention uses glycolic acid, acetic acid, anhydrous oxalic acid, and anhydrous citric acid as pore formers. The pore formers are added after part of the organic solvent has been added to the stirring tank, which can avoid the corrosion of the tank body by the acidic pore former. The pore former can be miscible with N-methylpyrrolidone to ensure the uniformity of the dispersion of the pore former in the slurry. By controlling the drying temperature of the electrode, controlling the volatilization speed of glycolic acid and acetic acid and the decomposition speed of anhydrous oxalic acid and anhydrous citric acid, the porosity of the electrode is improved, and the structure of the electrode is ensured not to be destroyed. The pore former used in the present invention is a weakly acidic substance, which can neutralize the residual alkali on the surface of the positive electrode material, adjust the pH of the slurry, and has the effect of alleviating the gelation of the slurry.

The invention relates to a lithium lanthanum zirconium oxide solid electrolyte coated graphite lithium ion battery negative electrode material and a preparation method thereof, and belongs to the technical field of lithium ion batteries. The method comprises the following steps: firstly, coating natural graphite with dopamine in a solution; uniformly mixing the dopamine coated graphite, lithium nitrate, lanthanum nitrate hexahydrate, zirconium oxychloride octahydrate, citric acid monohydrate and the like in deionized water; and performing high-temperature heat treatment on powder obtained after the solution is evaporated to dryness to obtain the lithium lanthanum zirconium oxide solid electrolyte coated graphite. According to the method, natural graphite is coated with dopamine in advance, the surface of the natural graphite is uniformly coated with lithium lanthanum zirconium oxide solid-state electric zirconium lysate without segregation by utilizing the amphiphilic property of the dopamine, and the cycle performance of the material is greatly improved while the rate capability of the material is ensured; the defects that the cycle life is not obviously improved and the rate capability is negatively influenced in the existing modification technology are overcome.

The present application relates to a sodium-supplemented diaphragm and a preparation method thereof, and a sodium-ion battery. The sodium-supplemented diaphragm includes a diaphragm substrate, a sodium-supplemented coating and an adhesive layer. The sodium-supplemented coating is coated on at least one side of the diaphragm substrate, and the adhesive layer is coated on the sodium-supplemented coating. The sodium-supplemented coating includes a sodium-supplemented additive, a first conductive agent, a first dispersant and a first binder. The adhesive layer includes a second binder, a second conductive agent and a second dispersant. The mass ratio of the second binder, the second conductive agent and the second dispersant is (60~95): (1~25): (3~20); the thickness of the adhesive layer is 0.3μm~5μm. The present application forms a strong bond between the diaphragm and the pole piece by setting an adhesive layer, effectively suppressing the generation of solid and gas residues after the sodium-supplemented agent reacts, the adverse effects on the interface contact between the diaphragm and the pole piece, and the problem of poor battery cycle stability.

The invention relates to a non-aqueous electrolyte and a lithium ion battery. In order to develop the sulfur-free electrolyte and the lithium ion battery with good high-temperature and cycle performance, the cycle performance, the high-temperature performance and the rate performance of the lithium ion battery are improved by compounding the additive A and the boron-containing lithium salt additive; furthermore, other components in the non-aqueous electrolyte are combined, so that the lithium ion battery still has more excellent high-temperature performance and cycle performance and more excellent safety performance and electrochemical performance when the voltage is increased to 4.5 V or even higher while the high-temperature performance and cycle performance of the lithium ion battery under conventional voltage are ensured. Wherein the structural formula of the additive A is as follows: R1 is selected from alkylene, fluoroalkylene, alkenylene or fluoroalkenylene, and R2 is selected from fluoroalkyl or fluoroalkenyl; and the additive B is boron-containing lithium salt.

The application relates to the technical field of battery positive electrode materials, in particular to a synergistically modified high-voltage positive electrode material and a preparation method and application thereof, which comprises a bulk particle, a doped layer coated on the surface of the bulk particle and a coating layer coated on the surface of the doped layer; the bulk particle comprises lithium nickel cobalt manganese oxide; the doped layer is lithium nickel cobalt manganese oxide doped with fluorine elements in a bulk phase; and the coating layer comprises a lithium fluoride coating layer and lithium nickel cobalt manganese titanium oxide particles embedded in the lithium fluoride coating layer. The preparation method comprises the following steps: firstly, a nickel cobalt manganese hydroxide precursor is prepared by adopting a coprecipitation method; then, a doped layer and a coating layer are synthesized on the surface of the nickel cobalt manganese hydroxide precursor by adopting a solvothermal method; finally, calcination treatment is carried out to obtain the synergistically modified high-voltage positive electrode material. The synergistic modification strategy of bulk phase doping and surface coating effectively guarantees the stability of the interface and bulk structure, the preparation process is simple, and the electrochemical performance of the positive electrode material under high voltage, high cycle, high rate or high-temperature environment is improved.

The embodiment of the invention provides a positive plate, a preparation method thereof and a secondary battery. The positive plate comprises a current collector, a first positive active layer and a second positive active layer which are sequentially stacked, wherein the first positive electrode active layer comprises a first positive electrode active material, a liquid ion plastic crystal electrolyte, a first conductive agent and a first binder, and the second positive electrode active layer comprises a second positive electrode active material, a solid ion plastic crystal electrolyte, a second conductive agent and a second binder. The liquid ion plastic crystal electrolyte with high ionic conductivity is used in the first positive electrode active layer, and the solid ion plastic crystal electrolyte with high electrochemical stability is used in the second positive electrode active layer, so that partition collaborative optimization of an ion transmission channel and interface stability is realized; and the problem of contact inactivation of the positive active material due to volume change in the charging and discharging process is further avoided, so that the rate capability and long cycle performance of the all-solid-state battery under low test pressure are ensured.

The application provides a positive electrode material, a preparation method and application thereof, and has the chemical formula of Li a Fe b (PO4) c @C; wherein 0.95<=a<=1.10, 0.95<=b<=1.05, and 0.95<=c<=1.05; and the primary particles of the positive electrode material are twinned crystals composed of multiple single crystals. The application provides a positive electrode material, a preparation method and application thereof, and can balance the processing performance and electrochemical performance of the positive electrode material, and improve the rate performance and cycle performance of the positive electrode material.

This invention belongs to the field of lithium-ion capacitor technology, specifically relating to a lithium-ion capacitor with a porous carbon positive electrode and a hard carbon negative electrode, and its preparation method. Pretreated coal powder and KOH powder are carbonized in a tube furnace at a mass ratio of 1:(3~5) to obtain porous carbon as the positive electrode material; the pretreated coal powder is carbonized in a tube furnace at 1200~1600℃ to obtain hard carbon as the negative electrode material; the positive and negative electrode materials are assembled at a mass ratio of (1~3):1 to obtain a lithium-ion capacitor with good electrical performance. The porous carbon prepared by this invention has a hierarchical pore structure, high specific surface area, and suitable defect density, providing high specific capacitance; the hard carbon prepared by this invention has a composite structure of short-range ordered graphite-like microcrystals and amorphous carbon, which is conducive to rapid lithium-ion insertion / extraction, providing a capacity basis; the appropriate assembly ratio of the porous carbon positive electrode material and the hard carbon negative electrode material effectively improves the overall performance of the lithium-ion capacitor.