Low Voltage Anodes for Lithium-Ion Batteries

Graphite has proved a highly successful anode for lithium ion batteries; however it is not without its limitations. There is intensive research to perfect silicon based anodes but important challenges still remain in the quest for high cycling efficiency and high cycle numbers. As a result, there remains much need for investigation of alternative anodes for lithium-ion batteries. Recently we investigated anodes based on LiVO2 1,2.  Intercalation into this compound, which is isostructural with LiCoO2, occurs in a two phase process with the formation of hexagonal close packed Li2VO2.1 We have now extended these studies to related compounds, and solid solutions, and have identified anodes with a capacity of over 215 mAh/g at C rate, Fig. 1. The density of these materials is 3.34 g/cm3 resulting in a volumetric capacity of 718 mAh/cm3 at 1C. Volumetric capacity is important for applications such as electric vehicles.  Detailed results of these investigations will be presented at the meeting. References: 1) A.R. Armstrong, C. Lyness, P.M. Panchmatia, M.S. Islam, P.G. Bruce, Nat. Mater. 10 (2011) 223-228. 2) F.d.r. Pourpoint, X. Hua, D.S. Middlemiss, P Adamson, D Wang, P.G  Bruce, C.P. Grey, Chem. Mater. 2012, 24, 2880−2893. Figure 1