Vacuum filtration-casted hierarchical carbon skeleton/TiO2 thick electrodes for lithium-ion batteries with high areal capacity

Abstract

Enhancing the areal capacity of lithium-ion batteries (LIBs) via designing of thick electrodes attracts significant interest. To promote this issue, carbon microfiber (CMFs) and carbon nanotubes (CNTs) are introduced as most electrode skeletons to improve the kinetics of the thick electrodes. Herein, self-supportive integrated thick electrodes with dual hierarchical carbon skeleton of CMFs and CNTs, and TiO2 are synthesized via vacuum filtration-casting technique. By tuning the ratio of both CMF and CNT, the optimized electrode achieves relatively high reversible areal capacity of 5.32 mAh cm−2@0.0125 A g−1, attractive rate performance of 0.91 mAh cm−2@0.50 A g−1 and impressive cyclic stability areal capacity of 2.75 mAh cm−2@0.10 A g−1 up to 150 cycles as anode material for LIBs. The enhanced performance can be attributed to the interconnected hierarchical carbon architecture and synergistic effect between the individual materials that facilitates better electrical conductivity for the rapid lithium-ion diffusion kinetics. Furthermore, in situ Raman analysis provides clear evidence for the rapid electronic/ionic transport kinetics in the proposed integrated architecture electrode. This work provides more options for the synthesis of thick electrodes for high performance and high areal capacity LIBs.