Engineering topics
Takeuchi, Esther (ORCID:0000000185181047)
Publications and source records attributed to Takeuchi, Esther (ORCID:0000000185181047).
Physics-Based Continuum Modeling for an Aqueous Rechargeable Zn/MnO 2 Battery
This study introduces a framework for modeling the aqueous Zn/MnO 2 rechargeable battery. A reaction system and a physics-based continuum model are proposed based on two reaction types, one involving insertion and the second related to dissolution and deposition of a solid reaction product. The model, fitted to empirical data, predicts voltage behavior and capacity limitations during cycling, identifying electrolytic zinc depletion as a limiting mechanism, depending on the original cell construction. The research suggests the need for further material characterization and reaction analysis, which will advance our understanding and facilitate the development of grid-scale energy storage solutions.
Enhancing composite electrode performance: insights into interfacial interactions
Propelled by the widespread adoption of portable electronic devices, electrochemical energy storage systems, particularly lithium-ion batteries (LIBs), have become ubiquitous in modern society.
Kinetic trapping of nanoparticles by solvent-induced interactions
Solvent-induced interactions produce the kinetic trapping of nanoparticles at nanoscale particle–wall separations.
Isothermal Microcalorimetry Analysis of Li/ β -MnO 2 Discharge
Despite widespread use over several decades, the lithium/manganese dioxide (Li/MnO 2 ) discharge mechanism is not completely understood owing to the structural complexity of the material. However, an improved understanding could lead to broader adoption as a primary and even secondary cathode material. Here, we examine the discharge of single-phaseβ-MnO 2 using isothermal microcalorimetry for the first time. Equilibrium voltage and entropy changes are characterized over the entire discharge range and used to rationalize the results. These measurements are supplemented by electrochemical impedance and X-ray diffraction data that give the clearest picture of theβ-MnO 2 lithiation process to date. We find that the first half of discharge is dominated by a two-phase reaction to form Li 0.5 MnO 2 followed by single-phase insertion to a composition of Li 1.0 MnO 2 , which confirms prior first-principles calculations. The tetragonalβ-MnO 2 lattice undergoes asymmetric expansion from Jahn-Teller distorted Mn 3+ to form an orthorhombic LiMnO 2 phase which retains the 1 × 1 tunnel structure. Microcalorimetry results suggest the presence of parasitic reactions occurring during the second half of discharge, which could arise from decomposition of electrolyte or release and reaction of residual water retained in the structure.