Issues and opportunities of manganese-based materials for enhanced Zn-ion storage performances

•The structure and performance of manganese-based compounds currently used in aqueous zinc-ion batteries is described.•Existing issues are analyzed in detail.•Modification approaches are summarized, including: Mn2+ addition in electrolyte, structural adjustment, functional modification and architecture construction.•The influence of diverse strategies on electrochemical performance is reviewed, and the prospects of various strategies are discussed.