High Temperature Electrochemistry IV: Session I
Sponsored by: TMS Extraction and Processing Division, TMS: Nuclear Materials Committee, TMS: Hydrometallurgy and Electrometallurgy Committee
Program Organizers: Prabhat Tripathy, Batelle Energy Alliance (Idaho National Laboratory); Guy Fredrickson, Idaho National Laboratory

Monday 2:00 PM
March 15, 2021
Room: RM 40
Location: TMS2021 Virtual

Session Chair: Uday Pal, Boston University, Boston, USA

2:00 PM
Selective Extraction of Gold from Gold-copper Alloy Using Anodic Electrochemical Deposition in Molten Salt Electrolyte: Takanari Ouchi¹; Shuang Wu¹; Toru Okabe¹; ¹The University of Tokyo
    The main metal component of waste printed circuit boards (WPCBs) is copper. In industrial recycling processes of gold from WPCBs, electrorefining in the copper smelting process, or hydrometallurgical leaching process by using cyanide or aqua regia solution, are employed as representative recovery processes. Recycling gold is time-consuming and generates large amounts of hazardous waste. In this study, direct extraction process of gold directly from gold-copper alloy, which is simple and does not generate harmful wastes, was developed. This process is based on the anodic electrochemical deposition of gold from its anionic ions dissolved in a molten salt electrolyte. Gold in copper was alloyed with sodium, and was then dissolved in a molten salt. The electrochemical behaviors of gold anions in the molten salt were investigated to demonstrate that pure gold was selectively obtained via anodic deposition. This result indicate the validity of the developed process to recycle Au from WPCBs.

2:30 PM
High-speed Electrodeposition of Textured Monolithic Lithiated Transition Metal Oxide Cathodes for Low Cost, High Energy, and Fast Charging Li-ion Batteries.: John Cook¹; ¹Xerion Advanced Battery Corp
    Xerion Advanced Battery Corp, founded in 2010, is in the process of commercializing a single-step molten hydroxide electroplating process to manufacture lithiated transition metal oxide (LTMO) cathodes. Xerion’s process benefits from the combined synthesis and electrode formation in just one step – revolutionizing the current commercial slurry-electrode manufacturing process (>20 steps). In this talk, the importance of crystal texture will be discussed. Xerion has found that controlling the crystal orientation improves the fast charge performance and delays the onset of thermal run-away. Furthermore, a business case will be provided for the use of LCO for automotive applications despite the current opinion that LCO is too expensive outside of the consumer electronic space. Xerion’s cost models show, at scale, our process can produce LCO / graphite cells at $45/kWh by utilizing low purity lithium and cobalt sulfate as opposed to battery grade >99.5% purity precursors.

3:00 PM  Cancelled
Characterization of Uranium Electrodeposits Separated in Molten ClLiK Salt with Varied Applied Overpotentials and Uranium-cerium Compositions: Dimitris Killinger¹; Supathorn Phongikaroon¹; ¹Virginia Commonwealth University
    Uranium electrodeposits, extracted in LiCl-KCl eutectic, were studied under varied overpotentials (25 mV, 50 mV, 100 mV, 200 mV) and molten salt weight concentration ratios of uranium to cerium (1:0, 1:1, 2:1) to investigate their effects on the morphology and chemical composition (purity) of the reduced uranium metal. Scanning electron microscopy with energy dispersive spectroscopy (SEM-EDS) capabilities was used to characterize the morphology and elemental surface composition of the collected uranium metal samples. Inductively coupled plasma mass spectrometry (ICP-MS) and x-ray diffraction (XRD) techniques were utilized for determining the overall composition of those samples. For the studied conditions, the final chemical compositions of the uranium electrodeposits indicate no correlation with varying the concentration ratios or overpotential, whereas morphology is greatly influenced with applied overpotential. A relationship between electrolytic time, electroactive working electrode surface area, and applied overpotential and their combined effect on electrodeposit growth is proposed and will be discussed.

3:30 PM
Molten Hydroxide Mediated Electrosynthesis of Layered Transition Metal Oxides for Electrochemical Energy Storage: Arghya Patra¹; Paul Braun¹; ¹University of Illinois at Urbana-Champaign
    Molten salt electrosynthesis is well developed at an industrial scale for the reduction of refractory elements and alloys. However, studies on multi-component systems grown by electrolytic oxidation are sparse. In this demonstration, we discuss a molten hydroxide mediated (LiOH, NaOH, KOH, CsOH and combinations thereof), intermediate temperature (250-350°C) electrocrystallization of alkali ion (Li⁺, Na⁺) intercalated transition metal oxides (Li₂MnO₃, LiMnO₂, LiNi_xMn_1-xO₄, LiCoO₂, NaCoO₂, NaMnO₂) in the form of tens of microns thick films. We explore the effects of electrodeposition parameters and solvent chemistry to formulate synthesis diagrams and probe mechanistic pathways across different transition metal chemistries. The conformally electroplated oxides provide unique opportunities as binder-and-additive-free, energy-dense cathodes for Li and Na ion battery.