Lithium secondary batteries using a lithium cobalt nitride, Li 2.6Co 0.4N, as the anode

Abstract

Lithium cobalt nitride, Li 2.6Co 0.4N, 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 Li 2.6Co 0.4N as the anode for lithium secondary batteries, possible combinations with cathode materials were considered: (1) Li 2.6Co 0.4N/Li 0.64Mn 1.96O 4 cell. Lithium ions were initially extracted from Li 1.05Mn 1.96O 4 by using Br 2 as an oxidant; (2) Li 2.6Co 0.4N/a-Cr 3O 8 cell, using a Li-free material of amorphous Cr 3O 8, which has a high lithium insertion capacity of more than 300 mAh/g; (3) Li 1.37Co 0.4N/Li 1.10Mn 1.90O 4 cell. Li 1.37Co 0.4N was used as the anode with the lithium chemically extracted. These lithium secondary batteries showed very high capacity.