The Surface-Treatment Of LiCoO₂ For Lithium Ion Battery

The market for Li-ion cells has rapidly expanded due to the increase in demand for mobile electronics. In this paper, a direct carbon-black coating has been applied to the cathode using an amphoteric-gelatin surfactant to fabricate a high-density Li-ion cell. By this method, the volumetric density and rate capability are improved without sacrificing electrochemical performance, compared with a conventional cell using bare LiCoO2.The currently available positive electrode is fabricated by dry-mixing an active material with a conductive agent, adding the mixture to a binder-containing solution to prepare a slurry, and coating the slurry onto a current collector and compressing it to thereby form an electrode. The conductive agent causes an increase in the thickness of the electrode.The aim of this thesis is to provide an active material for a battery having an excellent electrochemical characteristics and thermal stability, to provide a method of preparing an active material for a battery in a cost-effective manner with a high production efficiency, to provide a high-density electrode for a battery and to provide a battery that exhibits excellence in cell capacity and safety. The preparation technique of these active material results in a reduction of processing time compared to other techniques. In this thesis, these objectives are achieved using an active material for a battery according to an embodiment of method; the active material including with a conductive agent coating layer.The main contents of this thesis include the following:(1) The active material is prepared by preparing a coating liquid in which a conductive agent, two different dispersant in a solvent, adding the active material to the coating liquid such that the conductive agent is coated onto the surface of the active material, and heat treatment of the coated active material was carried out.(2) Effect of the amount of carbon black on capacity of circulation was examined; the optimal amount of carbon black can be getted by using...