Short Communication: Preparation and Electrochemical Performance of Mg-doped Li4Ti5O12 Nanoparticles as Anode Materials for Lithium-Ion Batteries

Abstract

Mg-doped Li4Ti5O12 nanoparticles with a grain size of around 200 nm were synthesized successfully using a simple solid-state reaction route. The effects of Mg2+ doping on Li4Ti5O12 were systematically investigated by XRD, XPS, TEM, HRTEM and EDS. These indicated that Mg ions were uniformly dispersed into Li4Ti5O12 lattice and Mg2+ doping during sintering can effectively inhibit the growth of Mg-doped Li4Ti5O12 particles without changing the structure of Li4Ti5O12. The charge-discharge cycling tests and EIS analysis were conducted to study their electrochemical performance. The initial discharge capacity of the Mg-doped Li4Ti5O12 electrodes was 190mAhg-1 at 1 C and the discharge capcity of 179mAhg-1 was retained after 100 cycles. Moreover, the discharge capacity of 150mAhg-1 was maintained even at a high rate of 5 C after 100 cycles, whereas the undoped electrodes only exhibited a capacity of 134mAhg-1 under the same condition. The excellent electrochemical performance of doped electrodes can be ascribed to the unique properties of nanomaterials and excellent electrical conductivity due to Mg2+ doping.