Synthesis And Lithium Insertion Properties Of Ramsdellite Lixtio2 Anode Materials

Ramsdellite LixTiO(2) (x=0.47) with reduced form is successfully prepared as a single phase by heating an amorphous lithium peroxo-polytitanate in 4.8% H-2 at 1100 degrees C for 0-1 h. The XRD data are well refined with the space group Pnma with a= 0.96076 nm, b =0.29514nm and c= 0.50276 nm. The ramsdellite LixTiO2 transforms into a rutile-ramsdellite intergrowth phase by extending the heating time to 1.25-4h. The capacity of the ramsdellite LixTiO2 in the region of 1.0-2.5V (vs Li) is 208 mAhg(-1) at 0.8 C rate (0.13 mA mg(-1)), substantially larger than that of the ramsdellite Li2Ti3O7 with oxidized form. The lithium insertion and deinsertion proceeds in two stages: a sloping region at higher potential (1.4-2.3 V) and a plateau region at lower potential (1.3-1.4V). (C) 2015 Elsevier Ltd. All rights reserved.