Low temperature lithium production

Patent metadata

Field	Value
Publication number	US-10718057-B1
Application number	US-201815925007-A
Country	US
Kind code	B1
Filing date	Mar 19, 2018
Priority date	Mar 19, 2018
Publication date	Jul 21, 2020
Grant date	Jul 21, 2020

Abstract

A method and electrolysis cell for producing lithium metal at a low temperature. The method includes combining (i) phenyl trihaloalkyl sulfone and (ii) an organic cation bis(trihaloalkylsulfonyl)imide or organic cation bis(trihalosulfonyl)imidic acid in a weight ratio of (i) to (ii) about 10:90 to about 60:40 to provide a non-aqueous electrolyte composition. A lithium compound selected from the group consisting of LiOH, Li2O and Li2CO3 is dissolved in the electrolyte composition to provide a soluble lithium ion species in the electrolyte composition. Power is applied to the electrolyte composition to form lithium metal on a cathode of an electrolysis cell. The lithium metal is separated from the cathode has a purity of at least about 95 wt. %.

First claim

What is claimed is:

1. A method of producing lithium metal in an electrolysis cell, the method comprising the steps of:
combining (i) phenyl trihaloalkyl sulfone and (ii) an organic cation bis(trihaloalkylsulfonyl)imide or organic cation bis(trihalosulfonyl)imidic acid in a weight ratio of (i) to (ii) of about 10:90 to about 60:40 to provide a non-aqueous electrolyte composition,
dissolving a lithium compound selected from the group consisting of LiOH, Li 2 O and Li 2 CO 3 in the electrolyte composition to provide a soluble lithium ion species in the electrolyte composition,
applying power to the electrolysis cell to form lithium metal on a cathode of an electrolysis cell,
separating lithium metal from the cathode, wherein the lithium metal on the cathode has a purity of at least about 95 wt. %.

2. The method of claim 1 , wherein the electrolyte composition further comprises a zwitterion or internal salt compound.

3. The method of claim 2 , wherein the zwitterion comprises a (carboxyalkyl)trialkyl ammonium compound.

4. The method of claim 1 , wherein heat is applied to the electrolyte composition at a temperature ranging from about 30° to less than about 100° C.

5. The method of claim 1 , wherein the electrolysis cell comprises an anode compartment, a cathode compartment and a separator between the anode compartment and the cathode compartment.

6. The method of claim 5 , wherein a weight ratio of soluble lithium ion species to electrolyte composition in the cathode compartment ranges from about 10:60 to about 10:25.

7. The method of claim 6 , wherein the separator is selected from the group consisting of a fritted glass separator, a microporous membrane, and a salt bridge.

8. The method of claim 1 , wherein the organic cation is selected from the group consisting of a phosphonium ion, a sulfonium ion, an ammonium ion, an imidazolium ion, a piperidinium ion, a pyridinium ion and a pyrrolidinium ion.

9. The method of claim 1 , wherein the halo ion is a fluoride ion of components (i) and (ii).

10. The method of claim 1 , wherein the alkyl group is a methyl group of components (i) and (ii).

11. The method of claim 1 , wherein power is applied to the anode and cathode at a current density ranging from about 0.1 mA/cm 2 to about 0.83 mA/cm 2 .

12. An electrolysis cell for producing lithium metal at a temperature below about 100° C. comprising:
a cathode compartment comprising a cathode,
an anode compartment comprising an anode,
a separator between the anode compartment and the cathode compartment
a non-aqueous electrolyte composition in the anode and cathode compartments comprising (i) phenyl trihaloalkyl sulfone and (ii) an organic cation bis(trihaloalkylsulfonyl)-imide or organic cation bis(trihalosulfonyl)imidic acid in a weight ratio of (i) to (ii) of about 10:90 to about 60:40, wherein the electrolyte composition further comprises a lithium compound selected from the group consisting of LiOH, Li 2 O and Li 2 CO 3 dissolved in the electrolyte composition,

whereby power applied to the anode and cathode forms lithium metal on the cathode of the electrolysis cell with a lithium metal purity of greater than 95 wt. %.

13. The electrolysis cell of claim 12 , wherein a weight ratio of soluble lithium ion species to electrolyte composition in the cathode compartment ranges from about 10:60 to about 10:25.

14. The electrolysis cell of claim 12 , wherein the electrolyte composition further comprises a (carboxyalkyl)trialkyl ammonium compound.

15. The electrolysis cell of claim 12 , wherein the separator is selected from the group consisting of a fritted glass separator, a microporous membrane, and a salt bridge.

16. The electrolysis cell of claim 12 , wherein the organic cation is selected from the group consisting of a phosphonium ion, a sulfonium ion, an ammonium ion, an imidazolium ion, a piperidinium ion, a pyridinium ion and a pyrrolidinium ion.

17. The electrolysis cell of claim 12 , wherein the halo ion is a fluoride ion of components (i) and (ii).

18. The electrolysis cell of claim 12 , wherein the alkyl group is a methyl group of components (i) and (ii).

Assignees

• Cons Nuclear Security Llc

Inventors

• Freiderich John W

Classifications

• C25C7/025

  used in cells for the electrolysis of melts · CPC title

• C25C7/00

  Constructional parts, or assemblies thereof, of cells; Servicing or operating of cells (for the production of aluminium C25C3/06 - C25C3/22) · CPC title

• C25C3/02 Primary

  of alkali or alkaline earth metals · CPC title

• C25C1/02 Primary

  of light metals · CPC title