Enabling high-performance multivalent metal-ion batteries: current advances and future prospects

The battery market is primarily dominated by lithium technology, which faces severe challenges because of the low abundance and high cost of lithium metal. In this regard, multivalent metal-ion batteries (MVIBs) enabled by multivalent metal ions (e.g. Zn²⁺, Mg²⁺, Ca²⁺, Al³⁺, etc.) have received great attention as an alternative to traditional lithium-ion batteries (Li-ion batteries) due to the high abundance and low cost of multivalent metals, high safety and higher volumetric capacities. However, the successful application of these battery chemistries requires careful control over electrode and electrolyte chemistries due to the higher charge density and slower kinetics of multivalent metal ions, structural instability of the electrode materials, and interfacial resistance, etc. This review comprehensively explores the recent advancements in electrode and electrolyte materials as well as separators for MVIBs, highlighting the potential of MVIBs to outperform Li-ion batteries regarding cost, energy density and safety. The review first summarizes the recent progress and fundamental charge storage mechanism in several MVIB chemistries, followed by a summary of major challenges. Then, a thorough account of the recently proposed methodologies is given including progress in anode/cathode design, electrolyte modifications, transition to semi-solid- and solid-state electrolytes (SSEs), modifications in separators as well as a description of advanced characterization tools towards understanding the charge storage mechanism. The review also accounts for the recent trend of using artificial intelligence in battery technology. The review concludes with a discussion on prospects, emphasizing the importance of material innovation and sustainability. Overall, this review provides a detailed overview of the current state and future directions of MVIB technology, underscoring its significance in advancing next-generation energy storage solutions.