The Preparation And Performance Of Porous Carbon And Carbon Composite As Lithium Ion Battery Anodes

Lithium ion batteries(LIBs) as a kind of environmentally friendly secondary power supply in today’s society, have attracted the wide attention. With the development of society, the demand for LIBs is also increasing. A very effective way to improve circulation performance and capacity of LIBs is to improve the anode materials’ performance and capacity of the LIBs. Carbon material is a kind of stable and environmentally friendly materials, and commonly used in LIBs. However, the current commercial graphite has a low theory capacity of 372 mAh/g. So scientists have took a lot of time to find out some new carbon materials with high capacity or carbon composite material, instead of graphite carbon anode materials. And typical representative of the cathode material with high capacity are nano-silicon and metal oxide anode materials.This paper was mainly focused on preparation, characterization and its application in LIBs cathode materials of the porous carbon materials and porous carbon-nanometer silicon and metal oxide composite materials. The concrete research included the following three aspects:1. The preparation of three-dimensional porous carbon materials based on metal organic frameworks as precursors. The method is simple and convenient and the morphology of porous carbon materials is special. Scanning electron microscopy, X-ray diffraction spectra and X-ray photoelectron spectroscopy were used to characterize the porous carbon materials. The performances of porous carbon materials as LIBs cathode materials were tested, founding that it had a high surface area of 1880 m2/g and still maintained a high specific capacity of 1015 mAh/g after 100 cycles as an anode material for lithium-ion batteries. The performance of the material is much better than the traditional graphite.2. In order to prepare LIBs cathode materials with high capacity, the zeolite imidazole frameworks(ZIFs) were grown on the nano-silicon, forming the unique ZIFs/nano-silicon composite materials. The resulted nano-Si/C nanocomposites as anode materials for LIBs showed a high reversible capacity of 1168 mAh/g at 100 mA/g after 100 cycles, which was higher than pure Si and many previously reported Si/C nanocomposites. It also showed an excellent performance. To support material synthesis provides a diversified way.3. The graphitization of carbon was prepared by calcining plants, generating the porous carbon as support materials. Then the Co3O4 with a size of 10 nm were grown on the porous carbon by the water thermal method. Its morphology was observed by Scanning electron microscopy and the performance of the batteries was explored, finding founding that it still maintained a high specific capacity of 1215 mAh/g after 100 cycles. It was better than many similar material. This approach is simple, flexible and low cost. It also can be mass production.