The olivine LiFePO 4 now stands as a competitive candidate of cathode material for the next generation of a green and sustainable lithium-ion battery system due to its long life span, abundant resources, low toxicity, and high thermal stability. In this review, we focus on LiFePO 4 and discuss its structure, synthesis, electrochemical behavior, mechanism, and the problems encountered in its application. The major goal is to highlight some recent development of LiFePO 4 with high rate capability, high energy density, and excellent cyclability resulting from conductive coating, nanocrystallization, or preparation.

A new anode material TiNb2O7 was synthesized by a sol−gel method. TiNb2O7 and its derivates display exciting performances at 1.3−1.6 V versus Li+/Li0, which is fully reversible and capable of fast charge and discharge rates.

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LiFePO 4 is a promising cathode material for the next generation of a lithium-ion rechargeable battery because of its low-cost, safety, excellent cyclability, and large capacity. Moreover, its voltage, 3.45 V versus lithium, is compatible with the window of a solid-polymer Li-ion electrolyte. Of particular interest for commercial applications is its safety and energy capacity at high power output and at short recharge times. We report here a systematic investigation of the enhancement of capacity at high rates of charge and discharge by substitution of a conductive, electrochemically active polymer for some or all of the deadweight conductive carbon and binder used conventionally to enhance performance of a secondary battery. Polypyrrole (PPy) and polyaniline (PANI) were used as the conductive polymers; two methods, electrochemical deposition and simultaneous chemical polymerization, were used to prepare the LiFePO 4 / polymer composite cathodes. Our results show that significantly improved capacity and rate capability can be achieved in such composite cathodes and that the electrodeposited carbon-coated LiFePO 4 /PPy composite exhibits the best performance.