Development of a Single-Walled Nanotubes Super Capacitor Electrode by AIST
Group of Japanese researchers at AIST have successfully developed a super capacitor electrode using single-walled carbon nanotubes (SWCNTs), which has been synthesized by water-assisted chemical vapor deposition. The researchers found that the aligned SWCNT ensembles have better electronic and ionic conductivities than activated carbon (AC) due to their cohesion, crystallinity, as well as absence of filling/binder material. Through this research, it was found that, fabricating electrodes purely from SWCNTs, with high carbon purity of 99.98%, a higher voltage range of 4 V was achieved in comparison to only 3 V for AC.
Furthermore, SWCNT based electrode maintains durability decline of only 3.6% over 1000 cycles at 4 V. In addition to this, due to their high electronic conductivity, the SWCNT electrodes are capable of operating without full coverage by metal current-collectors, contributing to a significant reduction in device weight. Performance of a SWCNT device without current-collectors is estimated for an energy density at 17 Wh/kg and for a maximum power density rating of 24 kW/kg.