Rechargeable metal-metal alkaline batteries: Recent advances, current issues and future research strategies

Over the past few decades, remarkable advancement has been attained in the field of rechargeable metal-metal alkaline batteries (RABs). In terms of safety, energy density, charge-discharge capacity, and long-term storage capability, metal-metal RABs (e.g., Ni-Zn, Ni-Fe, Ni-Bi, Ni-MH, Ag-Zn, Co-Zn, Cu-Zn, and Bi-Zn systems) are contemplated as the promising energy storage devices for the applications in electric vehicles (EVs), hybrid EVs, grid-scale energy storage, as well as various implantable and wearable electronic devices. Especially, Ni-MH batteries become competitive with Li-ion batteries for EVs and hybrid EVs applications due to their high tolerance against mechanical abuse, stability under wide temperature ranges, and considerable charge/discharge capacity. Meanwhile, earlier works reviewed only specific topics, so, as a rapidly growing research topic, providing a deep understanding on metal-metal RABs is timely and worthwhile. So, in this work, we discuss the electrochemistry of all metal-metal RABs, then full cell designing with their performance will be discussed thoroughly. Further, issues associated with the existing metal-metal RABs and corresponding improvement approaches will be provided for future advances in high-performance and reliable metal-metal RABs.

Automated summary

Remarkable advancements have been made in the field of rechargeable metal-metal alkaline batteries (RABs) in terms of safety, energy density, charge-discharge capacity, and long-term storage capability. Metal-metal RABs, such as Ni-Zn, Ni-Fe, Ni-Bi, Ni-MH, Ag-Zn, Co-Zn, Cu-Zn, and Bi-Zn systems, are considered as promising energy storage devices for electric vehicles, hybrid EVs, grid-scale energy storage, and implantable and wearable electronic devices. Ni-MH batteries have become competitive with Li-ion batteries in EVs and hybrid EVs applications due to their high tolerance against mechanical abuse, stability under wide temperature ranges, and considerable charge/discharge capacity.