Conducting network interface modulated rate performance in LiFePO ₄ /C cathode materials

Abstract

Abstract Carbon can play a critical role in electrode, especially for LiFePO 4 cathode, not only serving as continuous conducting network for electron pathway, but also boosting Li + diffusion through providing sufficient electrons. Here, we report the modulation of electrode/electrolyte interface to yield excellent rate performance by creating cross‐linked conducting carbon network in LiFePO 4 /C cathode material. Such conducting networks inhibit agglomeration and growth of LiFePO 4 /C primary particles and hence lead to a short Li + diffusion pathway. Furthermore, it also offers fast electron transmission rate and efficient electron for Li storage in the LiFePO 4 sheath. The LiFePO 4 /C with carbon nanotubes (CNTs) delivers a discharge capacity of 150.9 mAh·g −1 at 0.1C (initial Coulombic efficiency of 96.4%) and an enhanced rate capability (97.2 mAh·g −1 at 20.0C). Importantly, it exhibits a high cycle stability with a capacity retention of 90.3% even after 800 cycles at 5.0C (0.85 A·g −1 ). This proposed interface design can be applied to a variety of battery electrodes that face challenges in electrical contact and ion transport.