Lithium-ion batteries (LIBs) are powerful energy storage devices with several advantages, including high energy density, large voltage window, high cycling stability, and eco-friendliness. However, demand for ultrafast charge/discharge performance is increasing, and many improvements are needed in the electrode which contains the carbon-based active material. Among LIB electrode components, the conductive additive plays an important role, connecting the active materials and enhancing charge transfer within the electrode. This impacts electrical and ionic conductivity, electrical resistance, and the density of the electrode. Therefore, to increase ultrafast cycling performance by enhancing the electrical conductivity and density of the electrode, we complexed Ketjen black and graphene and applied conductive agents. This electrode, with the composite conductive additives, exhibited high electrical conductivity (12.11 S/cm), excellent high-rate performance (28.6 mAh/g at current density of 3,000 mA/g), and great long-term cycling stability at high current density (88.7 % after 500 cycles at current density of 3,000 mA/g). This excellent high-rate performance with cycling stability is attributed to the increased electrical conductivity, due to the increased amount of graphene, which has high intrinsic electrical conductivity, and the high density of the electrode.

Abstract
1. 서 론
2. 실험방법
3. 결과 및 고찰
4. 결 론
Acknowledgement
References

• 성기욱(서울과학기술대학교 신소재공학과) | Ki-Wook Sung (Department of Materials Science and Engineering, Seoul National University of Science and Technology)
• 안효진(서울과학기술대학교 신소재공학과) | Hyo-Jin Ahn (Department of Materials Science and Engineering, Seoul National University of Science and Technology) Corresponding author