High-Content N, O-Codoped C as Anodes for Lithium Ion Batteries

To develop high-capacity and low-cost carbon material, a novel high-content N, O-codoped C anode material is synthesized using melamine and glucose as starting materials. The as-prepared sample is composed of hierarchical meso-macroporous carbon bulks and graphene-like carbon sheets with 23.5 wt% N and 13.8 wt% O. The high-content N, O-codoped C exhibits high lithium storage capacity, long cycle life and excellent rate capability. At 200 mA g−1 over a voltage window of 0–3.0 V at 25°C, a discharge of about 670 mAh g−1 can be obtained after 500 cycles. Even at 1600 mA g−1, the high-content N, O-codoped C still exhibits a stable discharge capacity of 330 mAh g−1. Compared with the O-doped C and non-doped C materials, the high-content N, O-codoped C shows significant advantages in lithium storage performance, which are attributed to its high surface area, abundant porosity, graphene-like structure and rich heteroatom doping. With the rise of temperature, the lithium storage capacity of the high-content N, O-codoped C increases. With the decrease of delithation cutoff voltage, the reversible capacity of the high-content N, O-codoped C decreases. When assembled a full cell with the LiNi0.5Co0.2Mn0.3O2 cathode, a relatively stable cycling performance can be obtained.