Producing lithium

Abstract

A electrolytic process for continuous production of lithium metal from lithium carbonate or other lithium salts by use of an aqueous acid electrolyte and a lithium producing cell structure which includes: a cell body with a cathode within the cell body; an electrolyte aqueous solution within the cell body, the solution containing lithium ion and an anion; and a composite layer intercalated between the cathode and the electrolyte aqueous solution, the composite layer comprising a lithium ion conductive glass ceramic (LI-GC) and a lithium ion conductive barrier film (LI-BF) that isolates cathode-forming lithium from the electrolyte aqueous solution.

Description

[0001]This application claims the benefit of provisional application Ser. No. 61 / 844,482, filed Jul. 10, 2013, the disclosure of which is incorporated into this specification by reference in its entirety.BACKGROUND OF THE INVENTION[0002]The invention is a continuous process for obtaining lithium metal and a cell for carrying out the process.[0003]Lithium is a soft, silver-white metal belonging to the alkali metal group of chemical elements. It is the lightest metal and the least dense solid element. Lithium is highly reactive and flammable. Because of its high reactivity, it does not occur freely in nature, and instead, only appears in compositions, usually ionic in nature. Like the other alkali metals, lithium has a single valence electron that is easily given up to form a cation. Because of this, it is a good conductor of heat and electricity as well as a highly reactive element. Because of its reactivity, lithium is usually stored under cover of a hydrocarbon, often mineral oil. ...

AI Technical Summary

Benefits of technology

[0014]The invention provides an electrolysis cell and process characterized by a selective permeable barrier composite that provides for direct recovery of lithium metal. The cell and process are reasonably energy consuming and the lithium ion conducting composite layer is stable even in a highly corrosive anode compartment acid environment. In an embodiment, the invention is a lithium producing cell structure, comprising: a cell body with an anode and cathode within the cell body; an electrolyte aqueous solution within the cell body, the solution containing lithium ion; and a composite layer intercalated between the cathode and the electrolyte aqueous solution, the composite layer comprising a substantially impervious, lithium ion conductive composite layer (Li-GC) such as a glass ceramic and an active lithium ion conducting separation layer (Li-BF) that isolates cathode-forming lithium from the Li-GC.

Problems solved by technology

Lithium is highly reactive and flammable.

Previous lithium producing system have involved substantial capital and operating costs.

Additionally, Potter et al. points out that “[a]lkali metal ion conductors of this type are frequently not resistant to water and / or to alkali metals, and the experiment therefore leads to damage of the alkali metal ion conductors after only a short period.

This damage can comprise either mechanical failure of the ion conductor or loss of its conductivity.

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