System and process for producing lithium

Abstract

A decoupled plating system is provided for producing lithium. In a general embodiment, the present disclosure provides a feed tank configured to supply a lithium-rich aqueous electrolyte stream, a plating tank that is configured to receive an organic electrolyte and plate out lithium metal from that organic electrolyte, and one or more lithium replenishment cells configured to receive both electrolytes, keep them separated, and selectively move lithium ions from the aqueous electrolyte into the spent organic electrolyte stream. The present system and process can advantageously reduce operating costs and/or improve energy efficiency in production of lithium metal and associated products.

The invention is claimed as follows: 
     
         1 . A lithium producing system comprising:
 a plating tank configured to receive an organic electrolyte;   an anode provided within the plating tank;   a substrate spaced apart from the anode and provided within the plating tank, wherein the anode and the substrate are configured to apply a potential to the substrate, whereupon lithium is plated onto the substrate from the organic electrolyte, and a spent electrolyte stream is discharged; and   one or more lithium replenishment cells configured to receive the spent electrolyte stream and to form one or more regenerate electrolyte streams.   
     
     
         2 . The lithium producing system of  claim 1 , wherein the anode comprises a substantially planar mesh structure. 
     
     
         3 . The lithium producing system of  claim 1 , wherein the substrate comprises a substantially planar body portion. 
     
     
         4 . The lithium producing system of  claim 1 , wherein the plating tank includes one or more sidewalls, and the anode and the substrate are coupled to the one or more sidewalls. 
     
     
         5 . The lithium producing system of  claim 1 , wherein the substrate measures approximately 12.7 cm or greater in the longest dimension. 
     
     
         6 . The lithium producing system of  claim 1 , wherein the organic electrolyte comprises a DMC-LiPF6 mix. 
     
     
         7 . The lithium producing system of  claim 1 , wherein the one or more lithium replenishment cells are configured to receive both an aqueous and an organic electrolyte in separate streams, and wherein the one or more lithium replenishment cells comprise a lithium ion conductive glass ceramic that separates the organic electrolyte from the aqueous electrolyte. 
     
     
         8 . The lithium producing system of  claim 7 , wherein the aqueous electrolyte comprises lithium carbonate dissolved in sulfuric acid. 
     
     
         9 . The lithium producing system of  claim 7 , wherein the lithium ion conductive glass ceramic is an ion conductive glass-ceramic having the following composition in mol percent: P 2 O 5  26-55%; SiO 2  0-15%; GeO 2 +TiO 2  25-50%; in which GeO 2  0-50%; TiO 2  0-50%; ZrO 2  0-10%; M 2 O 3  0-10%; Al 2 O 3  0-15%; Ga 2 O 3  0-15%; Li 2 O 3 -25% and containing a predominant crystalline phase comprising Li 1+x (M, Al, Ga) x (Ge 1-y Ti y ) 2-x (PO 4 ) 3  where X≤0.8 and 0≤Y≤1 and where M is an element selected from the group consisting of Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm and Yb, and/or Li 1+x+y Q x Ti 2-x Si 3 P 3-y O 12  where 0<X≤0.4 and O<Y< 0 . 6 , and where Q is Al or Ga. 
     
     
         10 . The lithium producing system of  claim 7 , wherein the lithium ion conductive glass ceramic measures approximately 7.6 cm or less in the longest dimension. 
     
     
         11 . The lithium producing system of  claim 1  comprising a plurality of the lithium replenishment cells and/or plating tanks. 
     
     
         12 . The lithium producing system of  claim 1 , wherein the organic electrolyte is continuously provided to the plating tank, and the spent electrolyte is continuously regenerated at the one or more lithium replenishment cells and returned to the plating tank. 
     
     
         13 . A process for producing lithium, the process comprising:
 forwarding an organic electrolyte to a plating tank, wherein an anode and a substrate are provided within the plating tank;   applying a potential to the substrate, thereby plating lithium onto the substrate from the organic electrolyte and forming a spent electrolyte stream; and   regenerating the spent electrolyte stream within one or more lithium replenishment cells.   
     
     
         14 . The process for producing lithium of  claim 13 , wherein the anode comprises a substantially planar mesh structure. 
     
     
         15 . The process for producing lithium of  claim 13 , wherein the substrate comprises a substantially planar body portion. 
     
     
         16 . The process for producing lithium of  claim 13 , wherein the plating tank includes one or more sidewalls, and the anode and the substrate are coupled to the one or more sidewalls. 
     
     
         17 . The process for producing lithium of  claim 13 , wherein the organic electrolyte comprises a DMC-LiPF6 mix. 
     
     
         18 . The process for producing lithium of  claim 13 , wherein the one or more lithium replenishment cells are configured to receive both an aqueous and an organic electrolyte in separate streams, and wherein the one or more lithium replenishment cells comprise a lithium ion conductive glass ceramic that separates the organic electrolyte from the aqueous electrolyte. 
     
     
         19 . The process for producing lithium of  claim 18 , wherein the aqueous electrolyte comprises lithium carbonate dissolved in sulfuric acid. 
     
     
         20 . The process for producing lithium of  claim 18 , wherein the lithium ion conductive glass ceramic is an ion conductive glass-ceramic having the following composition in mol percent: P 2 O 5  26-55%; SiO 2  0-15%; GeO 2 +TiO 2  25-50%; in which GeO 2  0-50%; TiO 2  0-50%; ZrO 2  0-10%; M 2 O 3  0-10%; Al 2 O 3  0-15%; Ga 2 O 3  0-15%; Li 2 O 3 -25% and containing a predominant crystalline phase comprising Li 1-x (M, Al, Ga) x (Ge 1-y Ti y ) 2-x (PO 4 ) 3  where X≤0.8 and 0≤Y≤1 and where M is an element selected from the group consisting of Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm and Yb, and/or Li 1+x+y Q x Ti 2-x Si 3 P 3-y O 12  where 0<X≤0.4 and 0<Y≤0.6, and where Q is Al or Ga. 
     
     
         21 . The process for producing lithium of  claim 13 , wherein the spent electrolyte stream is regenerated within a plurality of the lithium replenishment cells. 
     
     
         22 . The process for producing lithium of  claim 13 , wherein the organic electrolyte is continuously provided to the plating tank, and the spent electrolyte is continuously regenerated at the one or more lithium replenishment cells. 
     
     
         23 . The process for producing lithium of  claim 13 , wherein the replenishment cell and the plating system are operated at different potentials to control a replenishment rate and a plating rate independently. 
     
     
         24 . A lithium producing system comprising:
 a plating tank configured to receive an organic electrolyte;   an anode provided within the plating tank;   a substrate spaced apart from the anode and provided within the plating tank; and   one or more lithium replenishment cells configured to receive the organic electrolyte stream from the plating tank, wherein the one or more lithium replenishment cells comprise a lithium ion conductive glass ceramic, and wherein the substrate is larger than the lithium ion conductive glass ceramic.