Functional binder engineering for Prussian blue analogue cathodes: mechanistic insights, cross-system inspiration, and design principles.

Being endowed with an open three-dimensional framework and cost advantage, Prussian blue analogues (PBAs) exhibit enormous application potential in the field of secondary batteries. However, their industrialization process is severely constrained by various failure mechanisms, such as structural distortion, manganese dissolution, and interfacial instability. Despite their critical role in maintaining electrode integrity and regulating interfacial chemistry, binder design in PBA systems has received insufficient attention. Here, we analyze the intrinsic correlations between PBA failure modes and the binder functionality, drawing inspiration from advanced strategies employed in silicon anodes, high-nickel cathodes, and LiFePO4 systems, including strong anchoring, self-healing, and conductivity enhancement. Based on this analysis, we systematically propose a design framework for multifunctional cathodic binders specifically tailored to PBAs. This review aims to provide systematic theoretical guidance and design strategies for constructing binder systems in high-performance PBA-based batteries.