리튬이차전지용 리튬분말음극의 표면개질에 관한 연구
- 발행기관 고려대학교
- 발행년도 2004
- 학위명 석사
- 학과 및 전공 고려대학교 대학원:신소재공학과
- 식별자(기타) DL:000005718274
- 본문언어 한국어
- 서지제어번호 000000870540
초록/요약 도움말
Lithium metal is an attractive material as a negative electrode in rechargeable batteries because of its high theoretical specific energy density (3860 mAh/g). However, poor cycle efficiency and safety problems caused by dendritic deposition of lithium metal have prevented lithium metal from being used in rechargeable batteries. It is generally known that the characteristics of the Li metal/electrode interface greatly affect the charge-discharge performance of a lithium metal anode. These studies have suggested that uneven current distribution caused by nonuniformity of the surface film on Li is the most probable reason for the dendritic formation during a charge. In order to suppress dendritic deposition, many researchers have tried to modify the morphology and properties of surface film on lithium. For example, they have investigated the effects of lithium salts, solvent systems, and additives such as CO₂ HF, iodide, Benzene and organic compounds. In previous papers, the compacted Li powder electrode has been suggested as a new anode material. Lithium powder was manufactured by droplet emulsion technique (DET). Compared with Li foil electrodes, a Li powder electrode has about four times a higher active surface area. This higher active surface probably lowers the effective current density in the electrode surface and thus, suppresses the dendritic formation of lithium. As liquid lithium was smashed during the DET process, a bare surface of lithium was created in silicon oil. Through the addition of surfactant material in silicon oil, the desired surface film on lithium powder may be obtained natively when the bare surface of lithium was formed. In addition, it is widely known that LiF film on Li electrode surface has enhanced electrochemical properties. In this study, surface modification was attempted to obtain desired LiF film on Li powder in the DET process by introducing a fluoride and the analysis of the surface state of Li electrodes was investigated to prove surface modification on a Li powder electrode.
more목차 도움말
Abstract = ⅰ
목차 = ⅲ
Ⅰ. 서론 = 1
Ⅱ. 이론적 배경 = 3
Ⅱ-1. Lithium metal battery = 3
Ⅱ-2. the Problem of Li metal battery = 6
Ⅱ-3. Li dendrite and SEI = 9
Ⅲ. 실험방법 = 13
Ⅲ-1. Powder making and surface modification = 14
Ⅲ-2. Powder compaction = 20
Ⅲ-3. Coin cell test = 22
Ⅲ-4. SEM observation = 24
Ⅲ-5. XPS(X-ray Photoelectron Spectroscopy) and EDX (Energy Dispersive X-ray) Analysis = 25
Ⅲ-6. Impedance Analysis = 26
Ⅳ. 실험결과 및 고찰 = 28
Ⅳ-1. Surface condition of surface modified Li powder electrode = 28
Ⅳ-2. Impeadance analysis of surface modified Li powder = 34
Ⅳ-3. SEM observation of various Li electrodes after electrodeposition = 38
V. 결론 = 42
참고문헌 = 44
