A new composite cathode-active material based on lithium manganese nickel oxide (LiMn2-xNixO4), poly(2,5-dimercapto-1,3,4-thiadiazole) (PDMcT) and polyaniline (PAni) was synthesized. The formation of the uniform and well-connected polymer film on the surface of LiMn2-xNixO4 particles was confirmed by Fourier-transform infrared spectra (FT-IR) and scanning electronic micrographs (SEM). The amounts of each constituent cannot be separately determined by thermogravimetric analysis (TGA). By galvanostatic charge-discharge tests, the PAni/PDMcT/LiMn2-xNixO4 composite showed a better electrochemical performance than each single component (PAni, PDMcT and LiMn2-xNixO4) and binary composites (PAni/LiMn2-xNixO4 and PDMcT/LiMn2-xNixO4). The electrical conductivity of the ternary composite reached 11.9 S cm(-1) and an initial discharge capacity of 305 mAh g(-1) was obtained. After 10 cycles, the coulombic efficiency and retention capacity was 99% and 90%, respectively. All results indicate a synergic effect among the materials in the composite. (c) 2008 Elsevier B.V. All rights reserved.