Lattice Bond‐Stiffness Topological Optimization Boosting High‐Rate Capability of LiMn 0.7 Fe 0.3 PO ₄ Cathode

Lithium manganese iron phosphate (LMFP) is a promising cathode material for lithium‐ion batteries (LIBs) due to its cost‐effectiveness, high safety, and high‐energy density. However, its practical deployment is critically hindered by sluggish Li + diffusion kinetics. Herein, we propose to utilize Zr 4+ as a lattice bond‐stiffness topological optimizer to reconstruct the atomic interaction landscape of LiMn 0.7 Fe 0.3 PO 4 . Through precise charge compensation and local strain engineering, the Zr 4+ dopant induces a unique stiff‐skeleton/flexible‐ion topological configuration. Specifically, it shortens the Mn/Fe─O bonds to rigidify the polyanionic framework against distortion, while simultaneously elongating the Li─O bonds to weaken the electrostatic confinement of Li + . Consequently, this bond‐stiffness modulation effectively decouples the tradeoff between structural stability and ionic mobility. The optimized LMZ 0.015 FP cathode delivers superior reversible capacities of 166.99, 136.13, and 119.01 mAh g −1 at 0.1, 20, and 50 C, respectively, along with outstanding cycling stability (99.6% retention after 300 cycles at 1 C). Even in a graphite||LMZ 0.015 FP full cell, a high capacity retention of 97.3% is maintained after 150 cycles. This work demonstrates that lattice bond‐stiffness topological engineering not only accelerates Li + diffusion kinetics and promotes a solid‐solution reaction pathway but also establishes a rational paradigm for designing next‐generation fast‐charging polyanionic cathodes.