Work

Comparison of electrochemical and hydrogen storage performance of Mg-rich alloys as negative electrode materials in Ni-MH batteries

Year: 2025

Type: article

Abstract: In this study, we aim to develop magnesium containing multicomponent anode materials to potentially replace rare earth elements in Nickel Metal Hydride (NiMH) batteries. Specifically, we investigate Mg 0.5 Al 12.5 Ni 12.5 Fe 12.5 Cr 12.5 high entropy alloys (HEAs) for application as NiMH anodes. These alloys were produced using Vacuum Arc Melting under an argon atmosphere and subjected to detailed phase, microstructural, and electrochemical characterizations. X-ray diffraction (XRD) and transmission electron microscopy (TEM) confirmed the formation of predominantly body-centered cubic (BCC) phases, along with minor hexagonal close-packed (HCP) phases. Electrochemical performance, assessed through charge-discharge cycling, yielded a maximum discharge capacity of 269 mAh/g ± 0.33 with a capacity retention rate of 51.85 % after 50 cycles. Electrochemical impedance spectroscopy (EIS) and hydrogen storage testing revealed rapid hydrogenation/dehydrogenation kinetics, with a maximum hydrogen absorption capacity of 2.04 wt% at 300 °C. These results highlight the potential of Mg 0.5 Al 12.5 Ni 12.5 Fe 12.5 Cr 12.5 HEAs for applications in hydrogen storage and electrochemical energy storage systems.

Source: International Journal of Hydrogen Energy

DOI: 10.1016/j.ijhydene.2025.151938

Authors: Gülhan Çakmak, Eli Grigorova, Berke Pişkin, Fatih Pişkin, Hakan Yüce

Institutions: Muğla University, Bulgarian Academy of Sciences, Institute of General and Inorganic Chemistry

Language: English

Topic: Hydrogen Storage and Materials

Subfield: Materials Chemistry

Field: Materials Science

Domain: Physical Sciences

SDG: Affordable and clean energy

Open Access status: hybrid

Estimated APC paid: $3,730