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Title: Defining the challenges of Li extraction with olivine host: The roles of competitor and spectator ions
The lithium supply issue mainly lies in the inability of current mining methods to access lithium sources of dilute concentrations and complex chemistry. Electrochemical intercalation has emerged as a highly selective method for lithium extraction; however, limited source compositions have been studied, which is insufficient to predict its applicability to the wide range of unconventional water sources (UWS). This work addresses the feasibility and identifies the challenges of Li extraction by electrochemical intercalation from UWS, by answering three questions: 1) Is there enough Li in UWS? 2) How would the solution compositions affect the competition of Li + to major ions (Na + /Mg 2+ /K + /Ca 2+ )? 3) Does the complex solution composition affect the electrode stability? Using one-dimensional olivine FePO 4 as the model electrode, we show the complicated roles of major ions. Na + acts as the competitor ion for host storage sites. The competition from Na + grants Mg 2+ and Ca 2+ being only the spectator ions. However, Mg 2+ and Ca 2+ can significantly affect the charge transfer of Li + and Na + , therefore affecting the Li selectivity. We point to improving the selectivity of Li + to Na + as the key challenge for broadening the minable UWS using the olivine host.  more » « less
Award ID(s):
2011854
NSF-PAR ID:
10400736
Author(s) / Creator(s):
; ; ; ;
Date Published:
Journal Name:
Proceedings of the National Academy of Sciences
Volume:
119
Issue:
31
ISSN:
0027-8424
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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