Non-alloy Mg anode for Ni-MH batteries
Multiple approaches towards a stable cycling performance
Yao Lin Xu (TU Delft - ChemE/Materials for Energy Conversion and Storage)
F.M. Mulder (TU Delft - ChemE/Materials for Energy Conversion and Storage)
More Info
expand_more
Other than for strictly personal use, it is not permitted to download, forward or distribute the text or part of it, without the consent of the author(s) and/or copyright holder(s), unless the work is under an open content license such as Creative Commons.
Abstract
Mg attracts much research interest as anode material for Ni-MH batteries thanks to its lightweight, cost-effectiveness and high theoretical capacity (2200 mA h g−1). However, its practical application is tremendously challenged by the poor hydrogen sorption kinetics, passivation from aggressive aqueous electrolytes, and insulating nature of MgH2. Mg-based alloys exhibit enhanced hydrogen sorption kinetics and electrical conductivity, but significant amount of costly transition metal elements are required. In this work, we have, for the first time, utilized non-alloyed but catalyzed Mg as anode for Ni-MH batteries. 5 mol.% TiF3 was added to nanosized Mg for accelerating the hydrogen sorption kinetics. Several strategies for preventing the problematic passivation of Mg have been studied, including protective encapsulation of the electrode and utilizing room-temperature/high-temperature ionic liquids and an alkaline polymer membrane as working electrolyte. Promising electrochemical performance has been achieved in this Mg–TiF3 composite anode based Ni-MH batteries with room for further improvements.
help_outline