Boron‐Catalyzed Graphitization Carbon Layer Enabling LiMn0.8Fe0.2PO4 Cathode Superior Kinetics and Li‐Storage Properties

Abstract The poor electrode kinetics and low conductivity of the LiMn 0.8 Fe 0.2 PO 4 cathode seriously impede its practical application. Here, an effective strategy of boron‐catalyzed graphitization carbon coating layer is proposed to stabilize the nanostructure and improve the kinetic properties and Li‐storage capability of LiMn 0.8 Fe 0.2 PO 4 nanocrystals for rechargeable lithium‐ion batteries. The graphite‐like BC 3 is derived from B‐catalyzed graphitization coating layers, which can not only effectively maintain the dynamic stability of the LiMn 0.8 Fe 0.2 PO 4 nanostructure during cycling, but also plays an important role in enhancing the conductivity and Li + migration kinetics of LiMn 0.8 Fe 0.2 PO 4 @B‐C. The optimized LiMn 0.8 Fe 0.2 PO 4 @B‐C exhibits the fastest intercalation/deintercalation kinetics, highest electrical conductivity (8.41 × 10 −2 S cm −1 ), Li + diffusion coefficient (6.17 × 10 −12 cm 2 s −1 ), and Li‐storage performance among three comparison samples (B‐C0, B‐C6, and B‐C9). The highly reversible properties and structural stability of LiMn 0.8 Fe 0.2 PO 4 @B‐C are further proved by operando XRD analysis. The B‐catalyzed graphitization carbon coating strategy is expected to be an effective pathway to overcome the inherent drawbacks of the high‐energy density LiMn 0.8 Fe 0.2 PO 4 cathode and to improve other cathode materials with low‐conductivity and poor electrode kinetics for rechargeable second batteries.