采用涂膜法和直接生长成膜法分别制备两种硅纳米线电极.XRD、SEM和充放电曲线表征、观察和测定材料嵌锂状态过程的结构、形貌及电化学性能.与涂膜法相比,直接生长成膜法制备的硅纳米线电极具有较高的比容量、良好的循环寿命及较好的倍率性能;直接生长成膜法制备的硅纳米线电极,其嵌锂过程硅由晶态逐渐转变为非晶态,且其纳米线直径逐渐增大,但线状结构仍保持完好,进而防止了电极粉化和脱落.
The SiNWs electrodes were fabricated by coating and direct growth methods, respectively. The structure, morphology and electrochemical performance of such materials were characterized by XRD, SEM and charge-discharge tests. The results show that the electrodes prepared by direct growth method had higher capacity, better battery life and also displayed and excellent cyelability at higher currents. During the process of lithiation, the initial crystalline Si transformed to amorphous LixSi, and the average diameter of the SiNWs increased. Despite the large volume changed, the SiNWs remained intact and did not break into smaller particles.