Preparation, Characterization And Application In Anode Material Of Lithium Ion Batteries Of New Carbon Materials

Carbon materials, possessing the advantage of low cost, rich raw material and novel physico-chemical properties, have been widely used in many fields such as catalyst, gas storage, sewage purify and anode materials. Now carbon materials have been paid more and more attention by scientists of chemical materials. Conventionally, external carbon sources are utilized during the synthesis of carbon material in the zeolites. In our work, the organic structure-directing agents have been directly used as carbon sources for the formation of non-graphitized carbon material in the zeolites. During the pyrolysis process, the interaction of the atoms of zeolites framework and carbon atoms results in the introduction of heteroatoms into the non-graphitized carbon material. The superior electrochemical performance of the obtained product as anode material for lithium secondary batteries has been studied. In addition, a microporous carbon with a narrow pore size distribution using an easily gained biomass as the precursor and carbon dioxide (CO₂) as the activating agent. The physico-chemical properties of the obtained product and its electrochemical performance as an anode material for lithium secondary batteries have been investigated.A non-graphitized carbon material was prepared via the utilization of a microporous crystalline silica-aluminum phosphate SAPO-44 containing organic molecules as a precursor. The carbon material is composed primarily of domains of disordered carbon layers and graphite micro-crystalline domains. During the pyrolysis process, some N and Si heteroatoms are introduced into the final non-graphitized carbon material via the direct rearrangement reaction of the raw organic molecules and the interaction between the carbon species and heteroatoms at the defects of the framework structure at high temperatures. The special composition and structure offer high charge/discharge capacity, good cycling performance, and a few or no decompositions of electrolyte on the surface of carbon material as anode material of lithium secondary batteries. This carbon material may help us gain further insights into the technical improvement in performance of carbon anode materials, especially in increasing reversible capacity and reducing irreversible capacity.A non-graphitized carbon material was also prepared from a magnesium-substituted aluminophophate MAPO-11. The carbon material is also composed primarily of domains of disordered carbon layers and graphite micro-crystalline domains. Elemental analysis indicates the existence of hetero atoms such as H, N and Al in the carbon material. The carbon material can give a considerable charge/discharge capacity and a good cycliability when it was used as the anode of lithium secondary batteries.A new microporous carbon with a narrow pore size distribution (1-2 nm) using carbon dioxide (CO₂) as the activating agent have been derived from an easily gained biomass - pinecone hull. The microporous carbon with H and N heteroatoms can give rise to high charge/discharge capacity and good cycling performance when it is used as an anode component for lithium secondary batteries and it can also reach its steady reversible capacity quickly at high current density.