Synthesis and electrochemical performance of Li4Ti5O12/Ag composite prepared by electroless plating

Abstract To improve the electrochemical and anti flatulence performance of Li 4 Ti 5 O 12 , Ag modified Li 4 Ti 5 O 12 (LTO) with high electrochemical performance as anode materials for lithium-ion battery was synthesized successfully by two-step solid phase sintering and subsequent electroless plating process in the presence of silver. The effect of Ag modification on the physical and electrochemical properties were investigated by the extensive material characterization of X-ray diffraction (XRD), Raman spectroscopy, scanning electron microscopy (SEM). The results showed that the samples possessed single spinel structure, it could be observed that the LTO/Ag composite and the pure LTO shared the same vibration frequencies, which indicated that the crystal structure of LTO didn’t change after electroless plating process, and the particles were uniformly and regularly shaped within 0.5–1.0 µm. Electrochemical performance of the samples were evaluated by the charging and discharging, cyclic voltammetry, electrochemical impedance spectroscopy, cycling and rate tests. It's obvious that the LTO/Ag composite prepared at the 10 min of electroless plating showed the highest performance with capacitance of 182.3 mA h/g at 0.2 C current rates. What's more, the LTO/Ag composites still maintained 92% of its initial capacity even after 50 charge/discharge cycles. Modification of appropriate Ag not only benefits the reversible intercalation and deintercalation of Li + , but also improves the diffusion coefficient of lithium ion. Besides, modification of appropriate Ag lower electrochemical polarization leads to higher conductivity and cycle performance of LTO, which is consistent with the results of the best reversible capacities.