Mesh-like LiZnBO3/C composites as a prominent stable anode for lithium ion rechargeable batteries

Abstract

Mesh-like LiZnBO₃/C composite was synthesized via a facile polymer pyrolysis method for use as an anode in lithium ion batteries (LIBs), demonstrating high initial capacity (860 mA h g⁻¹) and excellent cycle stability (559 mA h g⁻¹ after 600 cycles at 500 mA g⁻¹ with a capacity retention of 94.47%). Ex situ XRD tests indicate a mixed intercalation–conversion–alloy lithium storage mechanism in the first discharge/charge process of the composite. In addition, the LiZnBO₃/C anode was coupled with a commercial LiCoO₂ cathode in a full cell, which presented an initial reversible capacity of 658 mA h g⁻¹ at 100 mA g⁻¹ and a capacity of 603 mA h g⁻¹ after 400 cycles with average 0.02% fading in each cycle, which greatly outperforms previously reported compounds; this could be attributed to the unique mesh-like morphology of the composite, which enables high mass transport rate and good conductivity, and the coexistence of LiZnBO₃–ZnO–Zn composites that produce a synergistic effect for fast kinetics. This study holds great promise for LIBs with high capacity and good stability.