Recently nano-structured materials have been attracting much interest because they are distinguished from the conventional materials by their small particle size and large specific area giving rise potentially to remarkable electrochemical performance in electrodes [1,2]. Some researchers have reported the synthesis of nano-structured leady oxide for application as active materials in lead acid battery. Salavati et al. [3] reported that nano-size lead oxide powder with an average particle size of 35 nm could be synthesized by decomposing lead oxalate at 500 C. Karami et al. [4,5] synthesized uniform leady oxide nanostructures by the sonochemical method. The electrochemical tests showed a large
discharge capacity and excellent cycle characteristics, however the starting materials they used are pure chemical reagents, i.e.
Pb(NO3)2. In our previous researches [6,7], lead citrate
(Pb3(C6H5O7)2$3H2O) was synthesized from spent lead acid battery
pastes in citric acid system, and nano lead oxide with particle size of
100e200 nm was obtained from calcinationecombustion of lead
citrate.