Ferrous-cupric oxalate hydrate combined with multiwalled carbon nanotubes composite anodes for lithium-ion batteries

• Fe 2/3 Cu 1/3 C 2 O 4 · x H 2 O/MWCNTs was prepared by solvothermal method and self-assembly technique. • Cu fabricated in discharge process improves the activity of electrochemical products. • This unique design provides a new way for hydrated oxalate materials on lithium storage. Ferrous-cupric oxalate hydrate/multiwalled carbon nanotubes composite was prepared by solvothermal method and self-assembly technique. The structural and morphological characterization show that the CuC 2 O 4 · y H 2 O with three-dimension spherical shape is uniformly dispersed among the microrod-liked FeC 2 O 4 ·2H 2 O particles embedded by carbon nanotubes. Cu nanoparticles fabricated in first few cycles and carbon nanotubes provide a high conductivity, enhance electrical path for electrochemical reaction and improve the activity of complex nanocomposites, thus resulting in good lithium storage performance: 530 and 482 mAh g −1 at current densities of 0.5 and 2 A g −1 after 200 cycles. This unique design can shorten the preparation process, completely solve the decomposition of oxalate matrix and improve the homogeneity of synthetic materials.