A Porous Electrode Model for the Magnesiation and Demagnesiation of a Bismuth Electrode in Rechargeable Magnesium-Ion Cells

作者：Mayandi Ramanathan, Aadil Benmayza, Jai Prakash, Nikhilendra Singh, Fuminori Mizuno · 发表于：Journal of The Electrochemical Society · 年份：2015 · DOI：10.1149/2.0581603jes · 被引用次数：24 · 研究领域：Advancements in Battery Materials、Advanced Battery Materials and Technologies、Thermal Expansion and Ionic Conductivity

The transport and electrochemical properties of magnesium ions (Mg 2+ ) in a magnesium organohaloaluminate electrolyte were estimated experimentally. The key properties of a Bismuth (Bi) electrode; such as solid-state Mg 2+ diffusion, electronic conductivity, particle size, and electrode porosity were also estimated, both experimentally and theoretically. The magnesium organohaloaluminate electrolyte was utilized in an electrochemical cell to study the Mg 2+ insertion/extraction reactions in a Bi electrode. The existing porous electrode pseudo two-dimensional model was extended in the proposed study to describe the behavior of the α-Mg 3 Bi 2 /Mg cell system during charge-discharge reactions. The model was also modified to include experimentally evaluated parameters such as internal resistance, electrode kinetics, thermodynamics, and the diffusion of Mg 2+ in the active particles. This electrochemical model, modified with estimated parameters for the electrolyte, Mg, and α-Mg 3 Bi 2 electrodes, was formulated with both, direct 2-electron transfer and multi-electron transfer from each magnesium atom of the magnesium dimer present in the electrolyte. Details of the electrochemical performance from both mechanisms are compared with the experimental data, and factors governing the performance of the α-Mg 3 Bi 2 /Mg cell are discussed in the present study.