Electrochemical performance of a high-performance SiO composite anode material for Li-ion battery enhanced by piezoelectric effect

Silicon monoxide (SiO) anode is considered to be an ideal candidate anode material for lithium-ion batteries due to its high theoretical specific capacity, but usually limited by low electric conductivity and large volume changes during the charging-discharging cycle. Here, to overcome the drawbacks, we report a novel anode (SiO@C@Pb anode) prepared by doping lead titanate (PbTiO3) into SiO and graphite. The large volume expansion of SiO during the cycle causes the piezoelectric effect of PbTiO3. The piezoelectric effect can induce a micro-electric field, which reduces the resistance and accelerates the migration rate of lithium ion, so that, the composite electrode shows high coulombic efficiency and good lithium storage performance. As expected, the SiO@C@Pb anode shows a high initial discharge capacity (1264 mAh<middle dot>g-1), high initial coulombic efficiency (ICE, 83.45%), and capacity remained 1296 mAh<middle dot>g-1 after 80 cycles at a current rate of 0.1C. Moreover, the discharge capacity of SiO@C@Pb anode can be up to 226 mAh<middle dot>g-1 even at a current rate of 5C. Compared with the pristine SiO@C anode (833mAh<middle dot>g-1 initial discharge capacity, ICE, 78.62% at 0.1C, 55 mAh<middle dot>g-1 at 5C), the obtained SiO@C@Pb composite anode presents significantly improved electrochemical performance in terms of rate capability and cycling performance. The method of SiO-based electrode materials prepared in this work has the characteristics of simple process and low cost, which will provide a new idea for the preparation of high-performance lithium-ion batteries.