Li-Rich Mn-Based/Lithium Iron Phosphate Composite Cathode Material with Excellent Electrochemical Performance Enabled by Cooperative Shunting Mechanism

The commercialization of Li-rich Mn-based cathode materials (LR) is hindered by structural instability, voltage decay, and poor cycle performance. To address these challenges, we propose a cost-effective composite cathode material (LRLFP) by integrating LR with structurally stable LiFePO4 (LFP). The composite leverages a cooperative shunting mechanism: during high-rate discharge, current preferentially flows through the highly conductive LR component, ensuring high specific capacity, while LFP mitigates electrolyte erosion and stabilizes the interfacial structure. The LRLFP composite delivers discharge capacities of 211.3 mAh g–1 (0.1 C) and 139.6 mAh g–1 (5 C) within 2.0–4.6 V, with 92.55% capacity retention after 400 cycles at 1 C. At 55 °C, LRLFP retains 46.2% capacity after 300 cycles, outperforming standalone LR (4.9%) and LFP (12.8%). Characterization confirms that the LFP component suppresses structural degradation and voltage decay in LR, while the composite exhibits enhanced pseudocapacitive behavior and reduced charge transfer resistance (166.64 vs 252.23 Ω for LR). This work provides a simple yet effective strategy to synergize high capacity and structural stability, advancing practical applications of LR-based cathodes.