Lithium secondary batteries using a lithium cobalt nitride, Li2.6Co0.4N, as the anode

Lithium cobalt nitride, Li2.6Co0.4N, has a high capacity of 900 mAh/g with good cycle performance in lithium deintercalation and intercalation. The good reversibility and low potential in comparison to lithium metal (0.7 V on average) suggests that this nitride is a good candidate for an anode in a lithium secondary battery. In order to use Li2.6Co0.4N as the anode for lithium secondary batteries, possible combinations with cathode materials were considered: (1) Li2.6Co0.4N/Li0.64Mn1.96O4 cell. Lithium ions were initially extracted from Li1.05Mn1.96O4 by using Br2 as an oxidant; (2) Li2.6Co0.4N/a-Cr3O8 cell, using a Li-free material of amorphous Cr3O8, which has a high lithium insertion capacity of more than 300 mAh/g; (3) Li1.37Co0.4N/Li1.10Mn1.90O4 cell. Li1.37Co0.4N was used as the anode with the lithium chemically extracted. These lithium secondary batteries showed very high capacity.