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Abstract: A novel network LiFePO4/C composite was prepared by mixing precursor solution with carbon aerogel (CA) via a simple solution impregnation method, characterized by XRD, SEM, EDS and electrochemical analysis. The results revealed that the LiFePO4 nanowire forming on the ektexine of CA intertwined with LiFePO4/CA particles and formed a special web structure. The initial discharge capacity was improved to be 139.3 mAh g−1 at 10 C and the capacity retention is near 100% after 50 cycles. The web structure could improve electron transport and electrochemical activity effectively. [Copyright &y& Elsevier]

Abstract: La3+ and F− co-doped Li4Ti5O12 (LTO) anode materials are synthesized successfully via a solid state reaction. The structure and morphology are characterized by XRD, SEM and EDS. The results indicate that La3+ and F− ions were uniformly dispersed in Li4Ti5O12 lattice without changing the structure and morphology of Li4Ti5O12. Li3.95La0.05Ti5O11.7F0.3 (La005-F03) exhibits an outstanding electrochemical performance among all the samples in a potential range from 0.5 to 2.5 V, and delivers a discharge capacity of 103 mAh g−1 at 10C rate, whereas the LTO only gives 62.5 mAh g−1. The sample La005-F03 retains a discharge capacity of 170.1 mAh g−1 after 100 cycles at 1C rate. The improved electrochemical performance could be attributed to the appropriate co-doping with La3+ and F−, which can increase the amount of Ti3+/Ti4+ mixing as charge compensation, leading to the decrease of the charge transfer resistance and improvement of the electronic conductivity and lithium ion diffusion coefficient. [Copyright &y& Elsevier]