Synergistic intermolecular hydrogen‐bonded cross‐linking and steric hindrance effects enabling pomegranate‐type LMFP@C for Li ⁺ storage

Abstract

Abstract LiMn x Fe 1− x PO 4 is a promising cathode candidate due to its high security and the availability of a high 4.1 V operating voltage and high energy density. However, the poor electrochemical kinetics and structural instability currently hinder its broader application. Herein, inspired by the hydrogen‐bonded cross‐linking and steric hindrance effect between short‐chain polymer molecules (polyethylene glycol‐400, PEG‐400), the pomegranate‐type LiMn 0.5 Fe 0.5 PO 4 ‐0.5@C (P‐LMFP@C) cathode materials with 3D ion/electron dual‐conductive network structure were constructed through ball mill‐assisted spray‐drying method. The intermolecular effects of PEG‐400 promote the spheroidization and uniform PEG coating of LMFP precursor, which prevents agglomeration during sintering. The 3D ion/electron dual‐conductive network structure in P‐LMFP@C accelerates the Li + transport kinetics, improving the rate performance and cycling stability. As a result, the designed P‐LMFP@C has remarkable electrochemical behavior, boasting excellent capacity retention (98% after 100 cycles at the 1C rate) and rate capability (91 mAh·g −1 at 20C). Such strategy introduces a novel window for designing high‐performance olivine cathodes and offers compatibility with a range of energy storage materials for diverse applications.