A method to recycle graphite from lithium and sodium-ion batteries. Graphite from the batteries first is treated in an aqueous solution of strong base at a temperature range between about 100? C. and about 250? C., a pressure range between about 0.9 bar and about 20 bar, at a solid-to-liquid ratio of from about 1-to-1 to about 1-to-4. The treated graphite is then washed, filtered, and then treated with a mineral acid (e.g., hydrochloric acid). The purified graphite is then coated with amorphous carbon at a weight percentage range between 0.5 wt % and about 20 wt %. The recycled graphite yielded by the method routinely achieves a purity >99.9%, a specific area of less than or equal to about 10 m.sup.2/g.

Disclosed is a method for recovering a waste lithium cobalt oxide battery, the method comprising: feeding a lithium cobalt oxide battery black powder in a column-shaped container, adding a first acid to the column-shaped container for heat leaching until solids in the column-shaped container are not reduced any more so as to obtain a first leachate and leaching residues, wherein the first acid is a weak acid, and a filtering structure is arranged at the bottom of the column-shaped container; and adding a second acid to the column-shaped container containing the leaching residues for heat leaching until solids in the column-shaped container are not reduced any more so as to obtain a second leachate and graphite, wherein the second acid is a strong acid. According to the present invention, consumption of an inorganic strong acid can be reduced, emission of strong acid gas is reduced, and green and low-carbon heat leaching of the black powder is achieved.

A system and a method of continuously separating submicron thickness laminar solid particles from a solid suspension, segregating the suspension into a submicron thickness particle fraction suspension and a residual particle fraction suspension, the method comprising the steps of; providing a continuous centrifuge apparatus; providing a suspension of submicron thickness laminar solid particles in a solid suspension; wherein the solid suspension comprises the submicron thickness solid particles in a liquid continuous phase; separating the solid suspension in the apparatus.

A system and a method of continuously separating submicron thickness laminar solid particles from a solid suspension, segregating the suspension into a submicron thickness particle fraction suspension and a residual particle fraction suspension, the method comprising the steps of; providing a continuous centrifuge apparatus; providing a suspension of submicron thickness laminar solid particles in a solid suspension; wherein the solid suspension comprises the submicron thickness solid particles in a liquid continuous phase; separating the solid suspension in the apparatus.

Methods for the production in an electrochemical cell of graphene and graphite nanoplatelet structures having a thickness of less than 100 nm in a cell having a negative electrode which is graphitic and an electrolyte which consists of ions in a solvent, where the cations are sulfur-containing ions or phosphorus containing ions, wherein the method comprises the step of passing a current through the cell to intercalate ions into the graphitic negative electrode so as to exfoliate the graphitic negative electrode.

Methods for the production in an electrochemical cell of graphene and graphite nanoplatelet structures having a thickness of less than 100 nm in a cell having a negative electrode which is graphitic and an electrolyte which consists of ions in a solvent, where the cations are sulfur-containing ions or phosphorus containing ions, wherein the method comprises the step of passing a current through the cell to intercalate ions into the graphitic negative electrode so as to exfoliate the graphitic negative electrode.

A method of chemical oxidation and exfoliation of graphite ore using inorganic oxidizing potassium-type agents in an acid medium is disclosed. The product of the claimed method, according to electron microscopy analysis, is sheets or nanoscale graphene oxide plates with thicknesses less than 100 nm.

A method of chemical oxidation and exfoliation of graphite ore using inorganic oxidizing potassium-type agents in an acid medium is disclosed. The product of the claimed method, according to electron microscopy analysis, is sheets or nanoscale graphene oxide plates with thicknesses less than 100 nm.

Compositions and methods of producing discrete nanotubes and nanoplates and a method for their production. The discrete nanotube/nanoplate compositions are useful in fabricated articles to provide superior mechanical and electrical performance. They are also useful as catalysts and catalyst supports for chemical reactions.

The present disclosure relates to a reproduction method for obtaining a negative electrode active material with improved rapid charge-discharge property, from a used lithium ion secondary battery. A technology disclosed herein is directed to a reproduction method for a negative electrode active material from a used lithium ion secondary battery, including: a preparation step of preparing the used lithium ion secondary battery including a positive electrode, a negative electrode including a negative electrode active material containing a carbon material, and an electrolyte; a charging step of charging the lithium ion secondary battery; a discharging step of discharging the lithium ion secondary battery obtained after the charging step, at a discharge rate higher than a charge rate of the charging step; and a recovery step of recovering the negative electrode active material containing the carbon material from the negative electrode in the lithium ion secondary battery obtained after the discharging step.