Rana Lim, Minhee Lee and Jeom-Soo Kim*임라나·이민희·김점수*
Department of Chemical Engineering, Dong-A University, Busan 604-714, Republic of Korea동아대학교 화학공학과
A lithium is the lightest metal on the earth. It has some attractive characteristics
as a negative electrode material such as a low reduction potential (-3.04 V vs. SHE) and a
high theoretical capacity (3,860 mAh g-1). Therefore, it has been studied as a next generation
anode material for high energy lithium batteries. The thin lithium electrode is required to maximize
the efficiency and energy density of the battery, but the physical roll-press method has
a limitation in manufacturing thin lithium. In this study, thin lithium electrode was fabricated
by electrodeposition under various conditions such as compositions of electrolytes and the current
density. Deposited lithium showed strong relationship between process condition and its
characteristics. The concentration of electrolyte affects to the shape of deposited lithium particle.
As the concentration increases, the shape of particle changes from a sharp edged long one to
a rounded lump. The former shape is favorable for suppressing dendrite formation and the elec-trode shows good stripping efficiency of 92.68% (3M LiFSI in DME, 0.4 mA cm-2). The shape
of deposited particle also affected by the applied current density. When the amount of current
applied gets larger the shape changes to the sharp edged long one like the case of the low
concentration electrolyte. The combination of salts and solvents, 1.5M LiFSI + 1.5M LiTFSI
in DME : DOL [1 : 1 vol%] (Du-Co), was applied to the electrolyte for the lithium deposition.
The lithium electrode obtained from this electrolyte composition shows the best stripping efficiency
(97.26%) and the stable reversibility. This is presumed to be due to the stability of the
surface film induced by the Li-F component and the DOL effect of providing film flexibility.
Keyword : Lithium Metal Battery, High Energy Density, Advanced Anode Material, Electrodeposition,
Thin Lithium Electrode