Electrochemical Dilatometry Study on Si-Embedded Carbon Nanotube Powder Electrodes

Si-embedded carbon nanotube (Si–C/NT) powders were prepared by dispersing carbon nanotubes (CNTs) and Si in the tetrahydrofuran \nsolution containing poly(vinyl chloride) (PVC) as a dispersion agent, and then carbonizing the PVC. A better cycle \nperformance was observed with the Si–C/NT containing larger void volume. The origin of this feature was addressed by an \nelectrochemical dilatometry study, where it was found that the electrode swelling becomes less significant when the Si–C/NT \npossesses a larger void space. It is believed that the void space plays a buffering role against the volume expansion of Si, \nalleviating the breakdown of electrode integrity.