77results about How to "Mitigate capacity fading" patented technology

A rechargeable battery includes at least an electrolyte layer, a cathode layer and an anode layer. The electrolyte layer includes a lithium salt compound arranged between a cathode surface of the cathode layer and an anode surface of the anode layer. The anode layer is a nanostructured silicon containing thin film layer including a plurality of columns, wherein the columns are directed in a first direction perpendicular or substantially perpendicular to the anode surface of the silicon thin film layer. The columns are arranged adjacent to each other while separated by grain-like column boundaries running along the first direction. The columns include silicon and have an amorphous structure in which nano-crystalline regions exist.

The invention provides a lithium manganate material. The lithium manganate material comprises microspheres formed by a plurality of lithium manganate nanoparticles with the particle size of 10-200 nanometers, and a plurality of micropores are formed among the lithium manganate nanoparticles. The lithium manganate material is applied to lithium ion batteries, and the lithium manganate material of the structure is capable of shortening diffusion paths of ions, has large specific surface area to increase the contact area between the same and electrolyte and is capable of easing capacity fading of the lithium ion batteries in the charge-discharge process, so that cycling performance of the lithium ion batteries can be improved. The invention further provides a preparation method of the lithium manganate material.

Provided herein is a method of reducing the charge/discharge capacity fade rate of a rechargeable lithium-ion battery (LIB) during cycling, and extending the life and the number of discharge/recharge cycles thereof, effected by coating particles of lithium intercalation materials used for making the electrodes of the LIB, with a uniform layer of a metal fluoride effected by atomic layer deposition (ALD). Also provided are coated particulate lithium intercalation materials, electrodes and lithium-ion batteries having electrodes made with particulate lithium intercalation materials coated with a uniform later of a metal fluoride using ALD.

The invention provides a secondary battery based on a graphene aerogel/sulphur composite material. The invention discloses a secondary aluminum which comprises an anode, an aluminum-containing cathode and a non-aqueous electrolyte. The anode is made of the graphene aerogel/sulphur composite material, the cathode is made of metal aluminum or aluminum alloy, and the electrolyte is non-aqueous aluminum-containing electrolyte.

The invention provides a tetrafluoro-borate ion crosslinking hydroxyl polymer binding agent and a preparation method thereof. A polymer with a crosslinking network structure is formed by condensationreaction of tetrafluoro-borate ions formed by hydrolysis of a boride and hydroxyl on a hydroxyl polymer. The binding agent is high in tensile strength and high in elastic modulus and can bear stress generated by volume expansion and shrinkage of a negative active material of a secondary battery, and the volume change is effectively reduced; the active material and conductive additive particles canbe effectively coated by a three-dimensional network structure of the binding agent, favorable contact of the active material and the conductive additive is ensured, and the conductivity of an electrode plate is further ensured; and a hydroxyl group on the binding agent and the active material such as silicon can form a chemical bond, so that the bonding strength of the binding agent and the active material is improved. The invention also provides secondary battery negative paste, a secondary battery negative electrode and the secondary battery which are prepared by employing the tetrafluoro-borate ion crosslinking hydroxyl polymer binding agent.

Electrochemical cells that cycle lithium ions are provided. The electrochemical cells have an electrode that includes a silicon-containing electroactive material that undergoes volumetric expansion and contraction during the cycling of the electrochemical cell; and an electrolyte system that promotes passive formation of a flexible protective layer comprising a lithium fluoride-polymer composite on one or more exposed surface regions of the silicon-containing electroactive material. The electrolyte system includes a lithium salt, at least one cyclic carbonate, and two or more linear carbonates. At least one of the two or more linear carbonate-containing co-solvents is a fluorinated carbonate-containing co-solvent. The electrolyte system accommodates the volumetric expansion and contraction of the silicon-containing electroactive material to promote long term cycling stability.

The invention relates to a novel positive grid lead-calcium alloy for a lead-acid storage battery. The alloy is prepared from components in percentage by weight as follows: 0.05%-0.12% of calcium, 0.5%-1.5% of tin, 0.06%-0.11% of bismuth, 0.07%-0.15% of rare earth elements and the balance of lead, wherein the rare earth elements are one or more of ytterbium, gadolinium and lanthanum. The ingredients of the grid alloy are improved by adding tin, bismuth, the rare earth elements and other additives, and a novel deep-cycle and maintenance-free grid alloy material for the lead-acid storage batterywhich is corrosion-resistant, good in charging property and mechanical property and long in cycle life is obtained.

The invention provides a lithium-ion secondary battery with high reversible capacity and a manufacturing method thereof. The battery comprises a pole core, electrolyte and a metal shell, wherein the pole core and the electrolyte are accommodated in the metal shell; the pole core comprises a positive plate, a negative plate and a diaphragm positioned between the positive plate and the negative plate; the positive plate comprises a positive current collector and positive slurry coated on the positive current collector, and the negative plate comprises a negative current collector and negative slurry coated on the negative current collector; the battery also comprises a composite lithium plate, wherein the composite lithium plate is arranged in the metal shell; and the composite lithium plate comprises a metal matrix layer and a lithium coverage layer, the metal matrix layer is not dissolved in the electrolyte and does not undergo electrochemical reaction with the electrolyte, and the metal matrix layer is welded on the inner surface of the positive current collector or the negative current collector or the metal shell. Lithium ions consumed for forming a solid electrolyte interface (SEI) film can be effectively supplemented, and the utilization rate of lithium materials can be improved. The reversible capacity of the lithium ion battery can be improved, the irreversible capacity of the battery can be reduced, and the high reversible capacity of the battery can be kept.

The invention firstly provides a quasicrystal complex phase hydrogen storage alloy containing magnesium, titanium, vanadium and nickel and a preparation method thereof, belonging to the field of hydrogen storage materials. The expression formula of the hydrogen storage alloy is Ti1.4V0.6Ni+x% by weight of Mg, wherein x is more than 1 and less than 5. The invention further provides the preparation method of the quasicrystal complex phase hydrogen storage alloy containing the magnesium, the titanium, the vanadium and the nickel, and the method comprises the following steps: placing Ti, V and Ni metals into a vacuum electric arc furnace to smelt so as to form an alloy ingot, and preparing a Ti1.4V0.6Ni quasicrystal complex phase material thin strip containing an I phase through a vacuum sharp quenching and casting integrated machine; and then grinding, and placing magnesium powder into a ball milling tank for ball milling so as to get the hydrogen storage alloy, wherein the weight ratio of balls to material is (20-10): 1, and the ball milling time is 10-30min. Experimental results show that, after 50 cycles, the capacity decay rate of the quasicrystal complex phase hydrogen storage alloy containing the magnesium, the titanium, the vanadium and the nickel is far lower than the quasicrystal complex phase hydrogen storage alloy containing the titanium, the vanadium and the nickel.

The invention relates to a method for modifying a polyolefin lithium-ion battery separator, belonging to the field of lithium-ion battery separators. The method comprises the steps of: the step 1) immersing a pretreated polyolefin separator into a polycation electrolyte solution containing a calcium salt for 10-100 min, taking out and cleaning the pretreated polyolefin separator, then immersing the pretreated polyolefin separator into a polyanion electrolyte solution containing sodium silicate for 10-100 min, so that Ca2+ in the calcium salt and SiO32- ions of the sodium silicate react in situwhile the polycation electrolyte and the polyanion electrolyte are assembled according to electrostatic action to generate calcium silicate inorganic nano particles in the polyelectrolyte; repeatingthe steps for 1-6 times, and constructing organic/inorganic hybrid composite layers with different assembly layer numbers on the surface of the polyolefin porous separator; and then drying the organic/inorganic hybrid composite layers to finish the steps. The separator has better thermal stability and charge-discharge stability.

The invention provides a battery management device and a portable computer. The battery management device is used for managing a rechargeable battery arranged in the portable computer; the portable computer is provided with a charging circuit used for charging the battery; the battery management device comprises a discharging circuit used for discharging the battery, an acquisition module used for acquiring mode judging parameters, a first judging module used for judging whether the device is to be in a battery storage mode according to the mode judging parameters, and a first control module used for controlling the charging circuit or the discharging circuit to control the electric quantity of the battery in the battery storage mode so as to enable the electric quantity of the battery to be lower than a second electric quantity threshold; and the performance of the battery stored when the electric quantity is lower than the second electric quantity threshold is superior to that of the battery stored when the electric quantity is higher than the second electric quantity threshold. The battery management device postpones the capacity attenuation of the rechargeable battery of the portable computer.

The invention relates to a preparation method of a yolk-shell structure molybdenum disulfide@ carbon electrode material. The preparation method includes: utilizing molybdenum disulfide precursor solvothermal ethylene glycol to obtain monodisperse molybdenum disulfide nanospheres; allowing dopamine to self-polymerize on the interfaces of molybdenum disulfide particles to obtain a molybdenum disulfide@ polydopamine core-shell structure, and performing high-temperature carbonization on molybdenum disulfide@ polydopamine to obtain core-shell structure molybdenum disulfide@ carbon nanoparticles; dispersing molybdenum disulfide@ carbon in a hydrogen peroxide solution for hydrogen peroxide etching to obtain the yolk-shell structure molybdenum disulfide@ carbon material. A gap between molybdenum disulfide and a carbon shell can be well regulated by adjusting concentration of hydrogen peroxide. When the concentration of hydrogen peroxide is 0.4vol%, discharging specific capacity of a prepared yolk-shell structure molybdenum disulfide@ carbon lithium ion battery cathode in the second circle is up to 1167mAh g-1, discharging specific capacity after being circulated for 200 circles is 880mAh g-1, capacity retaining rate is 75.4%, and rate performance is outstanding.

The invention provides a high-specific-capacity metal organic negative electrode material of a secondary ion battery. A preparation method of the metal organic negative electrode material comprises the following steps: (1) mixing carboxylic acid containing a benzene ring, LiOH.H2O and metal salt according to the mol ratio of (0.8-1.2) to (0.5-1) to (0.25-1); then dissolving the mixture into absolute ethyl alcohol and ultrasonically stirring for 1h to 1.5h; (2) sealing a reaction solution obtained by the step (1) at 110 DEG C to 120 DEG C and reacting for 12h to 14h; and (3) washing a reactant obtained by the step (2) with de-ionized water and the absolute ethyl alcohol for 3-4 times respectively, centrifuging, drying an obtained solid at 70 DEG C to 80 DEG C for 6h to 8h and milling to obtain the product. By adopting organic salt formed by synthesizing metal salt and organic matters, organic energy storage and inorganic energy storage can be combined together, so that the prepared negative electrode material has a high specific capacity, high coulomb efficiency and excellent electrochemical circulating performance.

The invention discloses a preparation method of lithium iron borate. The preparation method comprises the following steps: mixing a lithium borohydride solution with a ferric nitrate solution and pouring a mixed solution into a sealed high-pressure reactor, carrying out hydrothermal reaction and then decompressing; absorbing the exported gas with ferric hydroxide slurry, adding aluminum citrate, uniformly stirring and mixing and then carrying out spray drying to obtain a dry material; sintering the dry material in an inert atmosphere, cooling to a temperature below 60 DEG C and discharging toobtain a calcined material; carrying out fluid energy milling on the obtained calcined material by using nitrogen, screening, removing iron and carrying out vacuum packaging to obtain a cathode material of the lithium iron borate. According to the preparation method of the lithium iron borate, disclosed by the invention, amorphous lithium iron borate is prepared by using the hydrothermal method, is coated with alumina citrate and is then calcined at high temperature to obtain the lithium iron borate coated with alumina and carbon; the lithium iron borate has the advantages of small primary particle size, good stability and good electrochemical property.