Modification Of Petroleum Coke As Anode Material For Lithium Ion Batteries

Petroleum coke has particular chemical, physical and mechanical properties, used widelyin many areas，especially in the lithium battery cathode carbon materials, petroleum cokeoccupies a particularly important position. The developmental direction of lithium battery isto achieve the level of high-efficiency, high-capacity, high current, which is particularlyimportant to the performance of the anode material. Petroleum coke is facile, low-priced andhigh current charge and discharge material, it is the preferred anode material for lithiumbatteries.In this paper, we make the petroleum coke as raw materials for lithium-ion batteries,using the methods of mechanical milling coating, LiF and AlF3modified coating, the redoxagent surface treatment material modification, doping coating and other methods to preparelithium-ion battery anode materials which have high capacity, high initial columbic efficiencyand superior cycling performance. We study the effect on the structure and electrochemicalproperties, such as the particle size, surface coating amount of petroleum coke and thesintering temperature and others have in lithium battery anode material.In this paper, we have prepared a composite having carbon/LiF (AlF3) a core/shellstructure by using modified doping method and mechanical milling. We have obtained thesample that its reversible capacity was250mA.h.g-1, the initial coulombic efficiency was75%and the coulombic efficiency still kept90%after50cycles. In some degree, the initialcoulomb efficiency and cycle characteristics of the petroleum coke have been improved.Modified by different coating methods and coating content, the petroleum coke anodematerial for lithium-ion have been prepared, which the capacity of the first coulombefficiency and cycle performance have been improved.We observed the microstructure and morphology by using the characterization methodsof XRD, SEM and so on; finally we have reached a conclusion that the best coating effect isto sinter12h at500oC. After a constant current charge-discharge, cyclic voltammetry andother electrochemical tests, we have investigated the effects of the electrical properties which the different amounts of fluoride coated had including reversible capacity, initialcharge-discharge efficiency etc.