Solid lithium electrolyte via addition of lithium salts to metal-organic frameworks

Patent metadata

Field	Value
Publication number	US-9525190-B2
Application number	US-201615083029-A
Country	US
Kind code	B2
Filing date	Mar 28, 2016
Priority date	Aug 10, 2012
Publication date	Dec 20, 2016
Grant date	Dec 20, 2016

Abstract

Various embodiments of the invention disclose that the uptake of LiO i Pr in Mg 2 (dobdc) (dobdc 4− =1,4-dioxido-2,5-benzenedicarboxylate) followed by soaking in a typical electrolyte solution leads to a new solid lithium electrolyte Mg 2 (dobdc).0.35LiO i Pr.0.25LiBF 4 .EC.DEC. Two-point ac impedance data show a pressed pellet of this material to have a conductivity of 3.1×10 −4 S/cm at 300 K. In addition, the results from variable-temperature measurements reveal an activation energy of approximately 0.15 eV, while single-particle data suggest that intraparticle transport dominates conduction.

First claim

We claim:

1. A method of forming a solid lithium electrolyte composition including a metal-organic framework comprises Mg 2 (dobdc), wherein dobdc=1,4-dioxido-2,5-benzenedicarboxylate and a lithium alkoxide comprising:
dissolving solid portions of H 4 dobdc and Mg(NO 3 ) 2 .H 2 O in a mixture of DMF, ethanol and deionized water and heating the solution to produce a solid;
soaking the resulting solid in DMF and then soaking in anhydrous methanol followed by filtering and evacuating the resultant solid to activate the metal-organic framework and form an activated framework;
reacting the activated framework with lithium isopropoxide in hexanes and collecting the sample by filtration and washing repeatedly with hexanes followed by evacuation; and
soaking the activated framework in a lithium tetrafluoroborate (LiBF4) solution including a mixture of ethylenecarbonate (EC) and diethylcarbonate (DEC).

2. The method of claim 1 , wherein the lithium alkoxide comprises lithium isopropoxide (LiO i Pr).

3. The method of claim 1 , wherein the lithium alkoxide comprises lithium ethoxide LiOEt).

4. The method of claim 1 , wherein the lithium alkoxide comprises lithium methoxide (LiOMe).

5. The method of claim 1 , wherein metal-organic framework comprises open metal cation Mg 2+ sites.

6. The method of claim 1 , wherein metal-organic framework further comprises lithium tetrafluoroborate (LiBF 4 ).

7. The method of claim 1 , wherein metal-organic framework further comprises ethylene carbonate (EC).

8. The method of claim 1 , wherein metal-organic framework further comprises diethyl carbonate (DEC).

9. The method of claim 1 , wherein the composition comprises Mg 2 (dobdc).0.35LiO i Pr.0.25LiBF 4 .EC.DEC.

Assignees

• Wiers Brian M
• Balsara Nitash P
• Long Jeffrey R
• Univ California

Inventors

• Wiers Brian M
• Balsara Nitash P
• Long Jeffrey R

Classifications

• H01M50/497

  Ionic conductivity · CPC title

• H01M10/0562

  Solid materials · CPC title

• H01M10/056 Primary

  characterised by the materials used as electrolytes, e.g. mixed inorganic/organic electrolytes · CPC title

• H01M10/0525

  Rocking-chair batteries, i.e. batteries with lithium insertion or intercalation in both electrodes; Lithium-ion batteries · CPC title

• H01M2/1646

  Electricity · mapped topic