Rechargeable Li-ion batteries (LIBs) have long been considered as an attractive power source for lots of mobile devices such as cellular phones, lap-top computers and electric vehicles. However, next generations of LIBs which are expected to have superior performance such as energy capacity, cycling stability and rate capability can only be achieved by making breakthrough in electrode materials. The SnO2/CNT hybrid materials have drawn much attention because their superior performance in LIBs. The incorporation of tin oxide nanoparticles into CNTs is expected to result in a high capacity and good cycle ability. For SnO2/CNT hybrids as an anode material, the CNTs can form a three dimensional electric network, and have high conductivity and large surface area. These properties are important for LIBs because they can strongly restrain the volume expansion or pulverization of electrode materials.

Recently, the Nanocomposite research group in Shanghai Institute of Ceramics has synthesized SnO2 nanoparticles coated on and filled into MWCNTs at 50 oC successfully by a simple solution method. The well crystallized SnO2 NPs have particle size of only 3-5nm. The discharge capacities showed that MWCNTs coated and filled with SnO2 had superior electrochemical performance. The first discharge capacities are 2127.4 and 1880.2 mAh/g at 70 and 200 mA/g and remain at 469 and 362 mAh/g after 40 cycles. Although a large capacity fade occurred in the discharge/charge cycles, the filled state SnO2/MWCNTs composite showed enhanced lithium storage properties than coated state.

The authors claimed that the better discharge/charge performance will be achieved if purity filled-state SnO2/MWCNT composites have been synthesized in future.

The related work has been published in Journal of Physical Chemistry C, 2009, 113(47), 20509(IF: 3.396). This work is supported by the 973 Project (2005CB623605), the Shanghai Nanotechnology Promotion Center (0852 nm01900) and Shanghai Talents Program Foundation.