Electrochemical behaviour of SnO2 doped with boron and indium in anodes for lithium secondary batteries

Nanoparticles of SnO2 were doped with boron and indium for use as active anode materials in non-aqueous lithium batteries. The cells thus obtained were found to exhibit between 1.0 and 0.0 V their best cycling properties. Undoped SnO2 and particularly low boron-doped samples exhibited the best electrochemical characteristics, as reflected in an increased specific capacity and in improved cycling properties. These cells retained 75% of their initial capacity after 30 cycles. By contrast, increased B content or doping with In caused a dramatic drop in capacity, in fact, cells hardly retained 30% of their initial capacity after only a few cycles. The adverse effects of the doping elements are ascribed to the poor electrochemical performance of bulk B2O3 and In2O3 rather than to other factors such as particle size, shape or crystallinity. (C) 1999 Elsevier Science B.V. All rights reserved.