New electrode materials for lithium rechargeable batteries

In this paper, a contribution to the search of new electrode materials for lithium batteries is reported. First, we will present the electrochemical behavior of an Aurivillius-type phase with the composition Bi4V2O11. This oxide may be used as cathode material (390 A h/kg) if the voltage is not so low (average voltage 1.6 V). On the other hand, if Bi4V2O11 is reduced down to 0.5 V, it reacts with 28 Li ions per formula unit. Considering only the low voltage region, Li28Bi4V2O11 could be a candidate to anode material (360 A h/kg at 0.7 V). Our research has also been directed towards the applications of several types of titanium oxides in lithium batteries. Among these compounds, we present the results for KxTi8O16 and Li2Ti3O7. The best results are those obtained from the ramsdellite Li2Ti3O7: the large reversibility, low polarization and relatively high capacity (235 A h/kg) make this compound a promising material as negative electrode for lithium ion cells. However, the relatively high average potential, close to 1.4 V, would reduce considerably the performance of a rocking-chair battery using this ramsdellite instead of carbon.