Type
Text
Type
Thesis
Advisor
Marschilok, Amy | Khalifah, Peter G | Parise, John.
Date
2014-12-01
Keywords
Chemistry | Electrochemistry, Lithium iron(II) indium phosphate, Phase discovery, Solid-state synthesis
Department
Department of Chemistry.
Language
en_US
Source
This work is sponsored by the Stony Brook University Graduate School in compliance with the requirements for completion of degree.
Identifier
http://hdl.handle.net/11401/77149
Publisher
The Graduate School, Stony Brook University: Stony Brook, NY.
Format
application/pdf
Abstract
Lithium iron(II) phosphate, also known as lithium ferrophosphate (LiFePO4, LFP), has been the subject of many recent energy storage studies. As a battery cathode material, LFP has many advantages for commercial applications. Compared to its competitors like LiMn2O4 and the ubiquitous but carcinogenic LiCoO2, LFP (specific energy = 600 Wh/kg) exhibits low toxicity, low cost, good thermal stability, and excellent electrochemical performance at high charge/discharge rates. As part of the efforts to understand and improve LFP, a great amount of research has been committed towards developing, characterizing, and electrochemically testing chemical relatives of this phase. In this work, chemical relatives of LFP belonging to the Li3PO4-Fe3(PO4)2-InPO4 phase system were investigated. This has lead to the discovery of lithium iron(II) indium phosphate [LiFeIn(PO4)2, LFIP]. Structural studies on LFIP using laboratory and synchrotron X-ray, neutron, and electron diffraction techniques have demonstrated this phase to crystallize in the orthorhombic space group Pbca with lattice parameters a = 9.276(1) Ã…, b = 13.757(2) Ã…, and c = 9.476(1) Ã…. Unlike LFP, this new material does not perform well as a battery cathode as found by chemical delithiation tests, electrochemical cycling, and bond-valence sum difference maps of Li+ diffusion pathways. LFIP has also been characterized by magnetic and optical measurements. The material does not order magnetically above 2 K, is paramagnetic with weak antiferromagnetic interactions, and has an effective magnetic moment of 5.39 µB/Fe. LFIP has a band-gap energy of 2.94 eV and d orbital ligand field splitting energies of 0.75 eV and 0.99 eV. Based on our synthesis results, a preliminary assessment of the Li3PO4-Fe3(PO4)2-InPO4 phase system is presented. | Lithium iron(II) phosphate, also known as lithium ferrophosphate (LiFePO4, LFP), has been the subject of many recent energy storage studies. As a battery cathode material, LFP has many advantages for commercial applications. Compared to its competitors like LiMn2O4 and the ubiquitous but carcinogenic LiCoO2, LFP (specific energy = 600 Wh/kg) exhibits low toxicity, low cost, good thermal stability, and excellent electrochemical performance at high charge/discharge rates. As part of the efforts to understand and improve LFP, a great amount of research has been committed towards developing, characterizing, and electrochemically testing chemical relatives of this phase. In this work, chemical relatives of LFP belonging to the Li3PO4-Fe3(PO4)2-InPO4 phase system were investigated. This has lead to the discovery of lithium iron(II) indium phosphate [LiFeIn(PO4)2, LFIP]. Structural studies on LFIP using laboratory and synchrotron X-ray, neutron, and electron diffraction techniques have demonstrated this phase to crystallize in the orthorhombic space group Pbca with lattice parameters a = 9.276(1) Å, b = 13.757(2) Å, and c = 9.476(1) Å. Unlike LFP, this new material does not perform well as a battery cathode as found by chemical delithiation tests, electrochemical cycling, and bond-valence sum difference maps of Li+ diffusion pathways. LFIP has also been characterized by magnetic and optical measurements. The material does not order magnetically above 2 K, is paramagnetic with weak antiferromagnetic interactions, and has an effective magnetic moment of 5.39 µB/Fe. LFIP has a band-gap energy of 2.94 eV and d orbital ligand field splitting energies of 0.75 eV and 0.99 eV. Based on our synthesis results, a preliminary assessment of the Li3PO4-Fe3(PO4)2-InPO4 phase system is presented. | 75 pages
Recommended Citation
Saccomanno, Michael Richard, "Synthesis and Characterization Studies of Li-Fe-In-(PO4) Phases: Chemical Relatives of Battery Cathode Material Lithium Iron Phosphate" (2014). Stony Brook Theses and Dissertations Collection, 2006-2020 (closed to submissions). 2985.
https://commons.library.stonybrook.edu/stony-brook-theses-and-dissertations-collection/2985