SHORT COMMUNICATION New NASICON type oxyanion high capacity anode, Li 2 Co 2 (MoO 4 ) 3 , for lithium-ion batteries: preliminary studies M. S. Michael & K. M. Begam & Michael Cloke & S. R. S. Prabaharan Received: 24 July 2007 / Revised: 12 October 2007 / Accepted: 20 October 2007 / Published online: 21 November 2007 # Springer-Verlag 2007 Abstract We describe in this paper the lithium insertion/ extraction behavior of a new NASICON type Li 2 Co 2 (MoO 4 ) 3 at a low potential and explored the possibility of considering this new oxyanion material as anode for lithium-ion batteries for the first time. Li 2 Co 2 (MoO 4 ) 3 was synthesized by a soft-combustion glycine-nitrate low temperature protocol. Test cells were assembled using composite Li 2 Co 2 (MoO 4 ) 3 as the negative electrode material and a thin lithium foil as the positive electrode material separated by a microporous polypropylene (Celgard® mem- brane) soaked in aprotic organic electrolyte (1 M LiPF 6 in EC/DMC). Electrochemical discharge down to 0.001 V from OCV (∼3.5 V) revealed that about 35 Li + could possibly be inserted into Li 2 Co 2 (MoO 4 ) 3 during the first discharge (reduction) corresponding to a specific capacity amounting to 1,500 mAh g -1 . This is roughly fourfold higher compared to that of frequently used graphite electrodes. However, about 24 Li + could be extracted during the first charge. It is interesting to note that the same amount of Li + could be inserted during the second Li + insertion process (second cycle discharge) giving rise to a second discharge capacity of 1,070 mAh g -1 . It was also observed that a major portion of lithium intake occurs below 1.0 V vs Li/Li + , which is typical of anodes being used in lithium-ion batteries. Keywords Anode materials . Lithium cobalt molybdate . Lithium-ion battery . NASICON structure Introduction Lithium-ion cells have emerged as the technology of choice to the world of portable electronics. The total sale of the cells is enjoying an increasing pace every year. Lithium-ion cells available in the market make use of LiCoO 2 [1] as conventional positive electrodes, and the materials for negative electrodes are generally carbonaceous composites [2] so as to maintain a high-voltage character. Carbona- ceous materials give a low voltage for lithium insertion/ extraction and a long cycle life. However, the capacity of these materials is 370 mAh g -1 , which is considerably smaller than the capacity offered by lithium metal [3]. With the objective of overcoming these problems and for improving the performance of lithium-ion batteries, plenteous materials have been studied as possible candidates as anode [4–8]. Innovative methods were implemented to identify the anodic behavior of a few lithiated transition metal oxides besides their well known cathodic performance [9, 10] though not impressive in terms of cathode point of view. Notably, inverse spinel LiNiVO 4 being regarded as a signature of high voltage class cathode material exhibiting a high working voltage ≥4.8 V vs Li/Li + offers inferior specific capacity as cathode in lithium batteries [9]. Nevertheless, it was found to show a good anodic behavior J Solid State Electrochem (2008) 12:1025–1029 DOI 10.1007/s10008-007-0456-4 DO00456; No of Pages Contribution to ICMAT 2007, Symposium K: Nanostructured and bulk materials for electrochemical power sources, July 1-6, 2007, Singapore. M. S. Michael Department of Chemistry, SSN College of Engineering, SSN Nagar, Kalavakkam, Chennai, India K. M. Begam Department of Electrical and Electronic Engineering, Universiti Teknologi PETRONAS, Tronoh, Malaysia M. Cloke : S. R. S. Prabaharan (*) Faculty of Engineering, The Nottingham University, Malaysia Campus, Semenyih, Malaysia e-mail: Prabaharan.Sahaya@nottingham.edu.my