| The graphite, as commercial anode material for lithium ion batteries, cannot meet the new requirement of high-performance lithium ion batteries because of its limited theoretical capacity of 372 mAh/g. Therefore, many kinds of new anode materials are being studied. Phosphorus has a high theoretical specific capacity (2596 mAh/g) and excellent rate performance, so it become the superior overall performance of the new anode material. Because of the low electronic conductivity, elemental phosphorus can not solely serve as anode materials. Also the nano-metal particles of metal phosphide easy to aggregate together in the process of charging and discharging, resulting in an unstable environment in the electrochemical materials. Therefore, phosphorus/carbon composites become the best choice as anode materials for lithium-ion batteries. This paper mainly focus on the high initial irreversible capacities and poor cycle performance of phosphorus/carbon composites. Combined with the present research on these composites, the improvement and design of its ingredients, preparation methods and structure were studied. The main contents are as follows:(1) Considering Multi-walled carbon nanotubes (MWCNTs) with high modulus and conductive properties and commercial red phosphorus (P) as the original materials, the P@MWCNTs composites with the structure of a thin amorphous red P layer coating on MWCNTs prepared by a wet ball-milling techniques and tested its electrochemical properties. The composites electrode presents a surprisingly high reversible capacity of 1396.6 mAh/g at 50 mA/g, giving an high initial coulombic efficiency of～77.94% and capacity retention of 90% over 50 cycles. Even at 1000 mA/g, it still maintains a superior specific reversible capacity of 934.0 mAh/g. When at current density 100,200, and even 500 mA/g, respectively, it still retained reversible specific capacity of 1374,1252.3,1095.3 and 934.0 mAh/g. These results show that:the amorphous red P was conducive to the diffusion of Li+, and the cladding structure greatly reduced the distance of electron conduction between MWCNTs conductive network and the amorphous red P, that immensely decreasing the transfer impedance of the electrode materiasl. MWCNTs not only improved the electronic conductivity of the whole materials, but also remitted the volume expansion of amorphous red P in lithium insertion and extraction reactions effectively. Therefore, P@MWCNTs composite is expected to be a high performance anode materials for lithium-ion batteries.(2) Regarding graphene having high specific surface area (2630 m2/g), good electrical properties and the advantages of high mechanical strength and flexibility, and further preparation of the GE@P composite anode material with graphene fold coated red phosphorus particles atomization drying technology and study its chemical properties of lithium storage. The 30%GE@P composites electrode presents a surprisingly high reversible capacity of 1030.3 mAh/g at 50 mA/g, and the reversible specific capacity of 50%GE@P also reached 700.7 mAh/g. When at current density 100,200,500 mA/g, and even 1000 mA/g,50%GE@P were still reversible specific capacities retention of 831.4,663.3,492.5 and 308.9 mAh/g. These results show that: the microparticle amorphous red P distributed on the graphene folds uniformly, which greatly increased the contact area and shortened the distance of electron conductivity between P and GE, and improved the overall conductivity of the material. The small space of graphene folds played a suppression and confinement role for the loss and volume expansion of P in lithium insertion and extraction reactions, respectively. Thus, GE@P composite is expected to become superior anode materials for lithium-ion batteries.
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