In this disclosure, a process of recycling acid, base and the salt reagents required in the Li recovery process is introduced. A membrane electrolysis cell which incorporates an oxygen depolarized cathode is implemented to generate the required chemicals onsite. The system can utilize a portion of the salar brine or other lithium-containing brine or solid waste to generate hydrochloric or sulfuric acid, sodium hydroxide and carbonate salts. Simultaneous generation of acid and base allows for taking advantage of both chemicals during the conventional Li recovery from brines and mineral rocks. The desalinated water can also be used for the washing steps on the recovery process or returned into the evaporation ponds. The method also can be used for the direct conversion of lithium salts to the high value LiOH product. The method does not produce any solid effluent which makes it easy-to-adopt for use in existing industrial Li recovery plants.

In this disclosure, a process of recycling acid, base and the salt reagents required in the Li recovery process is introduced. A membrane electrolysis cell which incorporates an oxygen depolarized cathode is implemented to generate the required chemicals onsite. The system can utilize a portion of the salar brine or other lithium-containing brine or solid waste to generate hydrochloric or sulfuric acid, sodium hydroxide and carbonate salts. Simultaneous generation of acid and base allows for taking advantage of both chemicals during the conventional Li recovery from brines and mineral rocks. The desalinated water can also be used for the washing steps on the recovery process or returned into the evaporation ponds. The method also can be used for the direct conversion of lithium salts to the high value LiOH product. The method does not produce any solid effluent which makes it easy-to-adopt for use in existing industrial Li recovery plants.

Provided herein are processes for recovering lithium ions from a brine source. The process can comprises increasing the pH of a brine source comprising lithium ions to at least about 5.5; contacting the pH-elevated brine source with a bed of protonated ion exchange media to produce a lithiated ion exchange media and a lithium-depleted brine stream; contacting the lithiated ion exchange media with an acidic aqueous wash liquid; and contacting the washed lithiated ion exchange media with an elution liquid comprising an acid. Also provided herein is a process for increasing the pH of brine comprising obtaining brine from a brine source comprising lithium ions; adding the brine to a continuously stirred tank reactor without preprocessing the brine to remove solid matter; adding a strong base to the continuously stirred tank reactor; contacting the brine with the base. Further provided herein are processes for creating a lithiated ion exchange media, which can comprise contacting a pH-elevated brine source with a bed of protonated ion exchange media; and producing a lithiated ion exchange media and a spent brine, wherein the bed of protonated ion exchange media comprises a metal oxide absorbent and a polymeric binder.

Provided herein are processes for recovering lithium ions from a brine source. The process can comprises increasing the pH of a brine source comprising lithium ions to at least about 5.5; contacting the pH-elevated brine source with a bed of protonated ion exchange media to produce a lithiated ion exchange media and a lithium-depleted brine stream; contacting the lithiated ion exchange media with an acidic aqueous wash liquid; and contacting the washed lithiated ion exchange media with an elution liquid comprising an acid. Also provided herein is a process for increasing the pH of brine comprising obtaining brine from a brine source comprising lithium ions; adding the brine to a continuously stirred tank reactor without preprocessing the brine to remove solid matter; adding a strong base to the continuously stirred tank reactor; contacting the brine with the base. Further provided herein are processes for creating a lithiated ion exchange media, which can comprise contacting a pH-elevated brine source with a bed of protonated ion exchange media; and producing a lithiated ion exchange media and a spent brine, wherein the bed of protonated ion exchange media comprises a metal oxide absorbent and a polymeric binder.

A negative electrode active material including a core, an intermediate layer on a surface of the core, and a shell layer on a surface of the intermediate layer, wherein the core includes a silicon oxide of SiO.sub.x (0<x<2); the intermediate layer includes a lithium silicate, the shell layer includes lithium fluoride (LiF) and the intermediate layer is present in an amount of 5 wt %-15 wt % based on a total weight of the negative electrode active material. Also, a method for preparing the negative electrode active material, and a negative electrode and lithium secondary battery including the same. The negative electrode active material provides excellent initial efficiency and life characteristics.

A sulfide solid electrolyte to be used in a lithium-ion secondary battery, including: a crystal phase; and an anion existing in a crystal structure of the crystal phase, in which the crystal phase includes an argyrodite crystal containing Li, P, S, and Ha; Ha is at least one element selected from the group consisting of F, Cl, Br, and I; the anion includes an oxide anion having a Q0 structure having an M-O bond that is a bond of M and O; and M is at least one element selected from the group consisting of metal elements and semimetal elements belonging to Groups 2 to 14 of a periodic table.

Provided are processes of removing lithium from an electrochemically active composition. The process of removing lithium from an electrochemically active composition may include providing an electrochemically active composition and combining the electrochemically active composition with a strong oxidizer optionally at a pH of 1.5 or greater for a lithium removal time. The electrochemically active composition may include Li, Ni, and O. The electrochemically active composition may optionally have an initial Li/M at % ratio of 0.8 to 1.3. According to some embodiments of the present disclosure, the lithium removal time may be such that a second Li/M at % ratio following the lithium removal time is 0.6 or less, thereby forming a delithiated electrochemically active composition.

Provided are processes of removing lithium from an electrochemically active composition. The process of removing lithium from an electrochemically active composition may include providing an electrochemically active composition and combining the electrochemically active composition with a strong oxidizer optionally at a pH of 1.5 or greater for a lithium removal time. The electrochemically active composition may include Li, Ni, and O. The electrochemically active composition may optionally have an initial Li/M at % ratio of 0.8 to 1.3. According to some embodiments of the present disclosure, the lithium removal time may be such that a second Li/M at % ratio following the lithium removal time is 0.6 or less, thereby forming a delithiated electrochemically active composition.

This invention relates to a method for the preparation of lithium carbonate from lithium chloride containing brines. The method can include a silica removal step, capturing lithium chloride, recovering lithium chloride, supplying lithium chloride to an electrochemical cell and producing lithium hydroxide, contacting the lithium hydroxide with carbon dioxide to produce lithium carbonate.

The present invention relates to a method for recovering a rare metal salt, the method including: an acid treatment step of obtaining a rare metal-containing acidic aqueous solution by bringing a material including a monovalent rare metal and a polyvalent rare metal into contact with an acidic aqueous solution; a separation step of obtaining permeated water including the monovalent rare metal and non-permeated water including the polyvalent rare metal from the rare metal-containing acidic aqueous solution by using a nanofiltration membrane satisfying the condition (1); and a concentration step of obtaining non-permeated water having a higher concentration of the monovalent rare metal and permeated water having a lower concentration of the monovalent rare metal than that of the permeated water in the separation step, by using a reverse osmosis membrane.