Multi-Ion Strategies Toward Advanced Rechargeable Batteries: Materials, Properties, and Prospects

As alternatives to conventional rocking-chair lithium-ion batteries (LIBs), novel rechargeable batteries utilizing abundant elements (such as sodium-ion batteries, potassium-ion batteries, and magnesium-ion batteries) have shown excellent performance. Nevertheless, these emerging batteries still face several challenges, including sluggish kinetics, limited reversibility, and a lack of suitable electrode materials. By incorporating carrier ions with different properties, hybrid-ion batteries (HIBs) based on multi-ion strategies have garnered extensive attention for their potential to solve most of these problems. However, with the increasing number of carrier ions that have been demonstrated to be suitable for multi-ion strategies, there exists deficiency in clarity regarding the nomenclature and classification of HIBs. For this reason, this comprehensive review offers an in-depth analysis of the fundamental configurations of HIBs according to the reaction mechanisms of the different carrier ions involved in the electrochemical redox reaction. Then, we systematically review the electrode materials for practical implementation on the basis of the energy storage mechanisms. Moreover, the challenges confronted by the current multi-ion strategies and promising future directions for overcoming these challenges are proposed for further research. The primary objective of this review is to inspire researchers in the rational design of highly efficient electrode materials for advanced HIBs.