Publications by authors named "J Kiggans"

Article Synopsis
  • Adding polyethyleneimine (PEI) to LiFePO4 nanoparticle suspensions enhances stability and decreases agglomerate size, improving lithium-ion battery cathode production.
  • The research identifies optimal PEI concentrations and molecular weights for stable suspensions: 1.5 wt% PEI (MW=2000 g/mol) for LiFePO4 and 5.0 wt% PEI (MW=10,000 g/mol) for Super P C45.
  • Separately dispersing LiFePO4 and Super P C45 improves the suspensions' properties, with dispersing LiFePO4 first leading to better overall performance, such as higher discharge capacity in half-cells.
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Neutron imaging is presented as a tool for quantifying the diffusion of ions inside porous materials, such as carbon electrodes used in the desalination process via capacitive deionization and in electrochemical energy-storage devices. Monolithic mesoporous carbon electrodes of ∼10 nm pore size were synthesized based on a soft-template method. The electrodes were used with an aqueous solution of gadolinium nitrate in an electrochemical flow-through cell designed for neutron imaging studies.

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Lithium-ion-conducting solid electrolytes hold promise for enabling high-energy battery chemistries and circumventing safety issues of conventional lithium batteries. Achieving the combination of high ionic conductivity and a broad electrochemical window in solid electrolytes is a grand challenge for the synthesis of battery materials. Herein we show an enhancement of the room-temperature lithium-ion conductivity by 3 orders of magnitude through the creation of nanostructured Li(3)PS(4).

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This report describes the efforts made to develop a resonant-ionization laser ion source based on tunable Ti:sapphire lasers for nuclear physics and astrophysics research at Holifield Radioactive Ion Beam Facility. Three Ti:sapphire lasers have been upgraded with individual pump lasers to eliminate laser power losses due to synchronization delays. Ionization schemes for 14 elements have been obtained.

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Addition of dispersants to aqueous based lithium-ion battery electrode formulations containing LiFePO(4) is critical to obtaining a stable suspension. The resulting colloidal suspensions enable dramatically improved coating deposition when processing electrodes. This research examines the colloidal chemistry modifications based on polyethyleneimine (PEI) addition and dispersion characterization required to produce high quality electrode formulations and coatings for LiFePO(4) active cathode material.

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