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LiFePO4/C ultra-thin nanoflakes have been synthesized via evaporative self-assembly induced by squaric acid and successfully applied for cathode materials in full cell. The morphologies and structures were characterized by X-ray diffractometer, scanning electron microscopy and transmission electron microscopy. Some LiFePO4/C nanoparticles about 40–80 nm in diameter are connected by LiFePO4/C ultra-thin nano-flakes which are constructed by squaric acids, other LiFePO4 nanoparticles are embedded in the ultra-thin carbon nanoflakes. LiFePO4/C ultra-thin nano-flakes deliver a initial discharge capacity of 164 mAh g−1 at 0.2C rate and 92 mAh g−1 at 50 C rate. Its capacity retention is still 96% at 10 C rate after 1000 cycles. The unique LiFePO4/C ultra-thin nano-flakes can effectively increase the contact between electrode and electrolyte, improve the electronic and ionic conductivity and promote the transportations for lithium ions.

Hierarchical porous LiFePO4/C composite has been successfully synthesised via evaporative self-assembly induced by vegetable proteins. The morphologies and structures are investigated by X-ray diffractometer, scanning electron microscope and transmission electron microscope. Hierarchical porous LiFePO4/C composite presents the connected hierarchical porous structure and nano-carbon network embedded in connected hierarchical pores. LiFePO4/C composite with 5 wt% vegetable proteins (LFP-5C) delivers a higher capacity of 166.8 mA h g−1 than LiFePO4/C composite with 8 wt% vegetable protein (LFP-8C) (161.4 mA h g−1) at 0.1 C rate. However, at a high rate of 30 C, LFP-8C exhibits a little higher discharge capacity of 148.6 mA h g−1and capacity retention of 97.3% after 100 cycles than LFP-5C (145.6 mA h g−1, 96.8%). The hierarchical porous LiFePO4/C composite is a promising material for practical application in lithium-ion battery.

LiFePO 4 /carbon nanowires with three-dimensional (3D) nano-network structure were successfully synthesized via evaporative self-assembly method induced by amylose. The morphologies and structures are investigated by X-ray diffractometer, scanning electron microscope and transmission electron microscope. The co-axis one-dimensional LiFePO 4 /C nanowires, which are 50 nm in diameter and between 400 nm and 1 μm in length, are tightly connected into 3D nano-network structure by the amorphous carbon from the short branched chains of amylase. They deliver high capacities of 167 and 138 mA h g −1 at 0.1 C and 50 C respectively. After 100 cycles at 50C rate, the capacity retention of the composite can still maintain 92.8% (128 mA h g −1 ).The unique 3D nano-network structure can effectively increase the contact between active materials and electrolyte, and improve the poor electronic and ionic conductivity.

Silicon/carbon microrods are co-deposited on copper substrate and graphite spheres surface using dimethyl dichlorosilance as carbon and silicon precursor. The obtained composites are characterized by X-ray diffraction and scanning electron microscopy. The experimental results show that silicon/carbon microrods deposited on the copper substrate, whose diameter is about 500 nm, are accumulated into sisallike morphology, those deposited on the graphite spheres surface form hedgehog-like feature, whose diameter is about 200 nm and whose top is like cauliflower. When current density of 50 mA/g is applied, charge capacity of silicon/carbon microrods is 1492 mA h/g (deposited on copper substrate) and 693 mA h/g (deposited on the graphite spheres surface). Moreover, silicon/carbon microrods deposited on the graphite spehres and copper substrate respectively deliver the capacity of 592, 985 mA h/g, and display no capacity decay at all after the 20 cycles, when cycled under current density of 500 mA/g.

LiFePO 4 and LiFePO 4 /C microspheres are successfully synthesized via facile co-precipitation in an elevated temperature oil bath. Their morphologies and structures are investigated by X-ray diffractometer, scanning electron microscope and transmission electron microscope. LiFePO 4 /C microspheres are uniform between 2 and 4 μm in diameter and composed of nanoparticles from 30 to 80 nm in size. Nanoparticles are coated by a thin nano-carbon layer and imbedded into three-dimensional nano-carbon networks. LiFePO 4 /C microspheres exhibit a high tap density (1.82 g cm −3 ), deliver large reversible discharge capacity of 165 mA h g −1 at 0.1C rate, excellent rate capability of 106 mA h g −1 at 50C rate, and capacity retention over 98% after 20 cycles even applied 50C rate. Therefore, the material is a potential candidate for high-power lithium ion batteries.

LiFePO4/C nanowires were successfully synthesized via evaporated self-assembly assisted by polyvinyl alcohol at room temperature. The structure, morphology, and composition of the as-prepared products were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), and thermogravimetric analysis (TG). The experimental results show that LiFePO4/C nanowires are uniform about 50–100 nm in diameter and 1 μm in length. LiFePO4/C nanowires exhibit excellent electrochemical performance and attain the discharge-specific capacity of 155 mAhg−1 at 1C rate and 118 mAhg−1 at 20C rate. The capacity retention is 98 % after 100 cycles at 20C rate.

Urchin-shaped Nb 2 O 5 microspheres have been synthesized through the facile hydrothermal method. Nb 2 O 5 microspheres, wrapped tightly by filaments about 10 nm in diameter and 1.5 μm in length, are about 0.8 μm in diameter. The initial discharge and charge capacities for Nb 2 O 5 microspheres are 480.43 mA h g −1 and 406.80 mA h g −1 at 50 mA g −1 , meanwhile it exhibits the capacity retention of 390.0 mA h g −1 after 200 cycles. The urchin-shaped Nb 2 O 5 microspheres are a potential anode material for lithium ion batteries.

Three-dimensional foam structure LiFePO 4 /C composite has been successfully synthesized via evaporative self-assembly assisted by polyethylene glycol. The morphologies, structures and properties of bare LiFePO 4 and LiFePO 4 /C are investigated by X-ray diffractometer, scanning electron microscope, and transmission electron microscope. LiFePO 4 /C composite exhibits high capacity of 150 mA h g −1 at the 1 C rate, and excellent rate performance (120 mA h g −1 at the 20 C rate). The improved properties can be attributed to a unique three-dimensional foam structure constructed by facile evaporative self-assembly. Furthermore, the unique structure can increase the electrochemical reaction surface, enhance the electrochemical conductivity and promote lithium ion diffusion.