The Lithium Storage Performance of Biochar-Loaded Metal Selenide Composite Material

Puffed rice carbon was obtained by carbonizing puffed rice at high temperature. Puffed rice carbon (used as biochar) and commercial Sn and Se powder were used to design SnSe/PRC anodes for lithium ion batteries with a high-energy ball grinding method under inert argon atmosphere with 600 r/m for 48 hours. The structure, morphology and electrochemical property of the materials were characterized with X-ray diffraction, scanning electron microscopy (including energy dispersive spectrometer), galvanostatical cycling tests, cyclic voltammetry and electrochemical impedance spectroscopy. Under the action of high energy mechanical force, puffed rice carbon, Sn and Se powder extruded each other to form an alloy/carbon inlaid structure, which improved the electrical conductivity, buffered the large volume expansion effect and improved the structural stability. When cycled at a current density of 500 mA/g in 0.01~3.00 V, SnSe/PRC presented a high initial discharge capacity of 703.9 mAh/g and retained a stable capacity of 608.9 mAh/g after 50 cycles. It also had a good rate performance. Its capacity remained stable under high current densities. When the initial current density was restored, the capacity returned to the initial level. The research shows that the utilization of this environment-friendly and facile biochar can effectively improve the lithium storage performance of SnSe, which has a good reference value for the application of metal selenide in the lithium ion battery.