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Nanostructured mesoporous LiFePO4/C (LFP/C) composite was prepared by spray-drying-assisted solid-state reaction with FeSO4 and LiOH as reactants. Instead of tubular furnace in various atmospheres (nitrogen or argon) of the calcination method, box furnace embedded with biomass waste rice husk char as embedded agent did not need to supplement atmosphere method was first applied in this study. The influence of micro-reducing atmosphere on the phase formation and particulate morphology of product was systematically investigated by XRD, SEM, TEM, XPS and Raman techniques. Rice husk char embedded was beneficial to the formation of LFP/C materials with good electrochemical performance and high stability. XRD and Raman test results show that pure LFP material can be prepared in the micro-reducing atmosphere, and the addition of glucose is conducive to the formation of crystallized carbon network. XPS of LFP/C materials demonstrate the micro-reducing atmosphere is conducive to the reduction of Fe3+ to Fe2+. Cathodes of LFP/C provided specific discharge capacities of 158 mA h/g and 128 mA h/g at 0.2 C and 10 C, respectively. The low cost spray-drying-assisted solid-phase reaction may be a practical way for the economic synthesis of LFP/C as high-rate electrodes of lithium-ion batteries. [ABSTRACT FROM AUTHOR]

The LiFePO4 with olivine structure has become one of the most popular cathode materials for lithium-ion batteries due to its absolute superiority of safety, environment-friendly, inexpensive. In this paper, Fe3(PO4)2 and Li2CO3 were used as raw materials, meanwhile graphite powder or glucose as reducing agent to prepare the LiFePO4 cathode materials via carbothermal reduction method. The effects of molar ratio of lithium to iron, calcination temperature, calcination time, C% and the different C resource on the phase, morphology and electrochemical properties of the products were investigated. The experimental results showed that when the molar ratio of LiFePO4 was 1.05, the calcination temperature at 750 °C for 3 h, and graphite powder or glucose content 5%, the pure olivine structure LiFePO4 sample was obtained, the particle size of which was about 2 ∼ 5 μm with good dispersibility. The prepared sample was assembled as CR2032 Button Battery for electrochemical performance. The charge-discharge capacity was close to the theoretical capacity of 170mAh/g, the efficiency was more than 99% and high-rate capacity retention was maintained at 96.5%, respectively. The overall electrochemical performance of LiFePO4 was excellent. [ABSTRACT FROM AUTHOR]

Using metatitanic acid and lithium hydroxide as raw material, lithium ion battery cathode material Li4Ti5O12 was prepared by one step hydrothermal ion exchange synthesis method. The effects of molar ratio of Li and Ti, reaction temperature and reaction time were investigated respectively. The prepared lithium titanate was characterized by XRD and SEM for the structure and morphology and tested the battery performance through assembling the CR2016 lithium ion button battery. Experimental results showed that pure spinel type lithium titanate can be obtained when molar ratio of Li and Ti was 0.85, reaction temperature was 170°C࿵ E; 200°C after 24 h reaction, of which the diffraction peaks were one to one corresponding to diffraction peaks in the standard card (PDF#26-1198). The products were of good electrical properties, when the rate was 0.1C, the first charge/discharge capacity reached 165.2 mAh/g, the capacity retention rate was 97% after 30 charge/discharge cycles. [ABSTRACT FROM AUTHOR]