Amorphous Si film anode coupled with LiCoO2 cathode in Li-ion cell
An amorphous silicon film was deposited on copper foil by a physical sputtering method and coupled with commercial LiCoO2 cathode to fabricate full cells. Their cycle performance and high rate capability at room temperature have been investigated. In the voltage range 2.5-3.9 V at the current density of 0.1 mA/cm2 (0.2 C), the lithiation and delithiation capacity of this full cell was first increased to 0.55 mAh/cm2 within 80 cycles and maintained stable during the following cycles. After 300 cycles its capacity still retained 0.54 mAh/cm2. High-resolution transmission electron microscopy (HRTEM) and selected area electron diffraction (SAED) image indicated that the sputtered film could keep an amorphous structure although the volume expansion ratio during the lithiation and delithiation was still up to 300％ after 300 cycles observed from scanning electron microscopy (SEM) image. This recovered amorphous structure was believed to be beneficial for the improvement of the cycle life of the full cell. Rate performance showed that the full cell had a promising high rate capability. At 30C, its lithiation/delithiation capacity remained 25％ of that at 0.2 C.
Physical sputtering Amorphous silicon film Full cell Cycle life Rate capability
Mengtao WU Huabin YANG Laihe HUANG
Tianjin B&M Science and Technology Joint-Stock Co., Ltd., Tianjin 300384, China
国际会议
深圳
英文
31-34
2007-01-17（万方平台首次上网日期，不代表论文的发表时间）