Cable-like Heterogeneous Porous Carbon Fibers with Ultrahigh-Rate Capability and Long Cycle Life for Fast Charging Lithium-Ion Storage Devices
In this paper, we propose a space-confined foaming approach to fabricate a cable-like heterogeneous porous carbon fibers (Si-CPCFs) containing the inner graphitized carbon “conductor” and the outer Si-doping amorphous carbon “shield”. Benefited from the fast Li+ intercalation and high conductivity of the “inner conductor”, and the rich pseudocapacitance of the “outer shield”, the Si-CPCFs exhibite an ultrahigh-rate capability and cycling performance, leading to a high capacity of 132 mAh g-1 even at an ultra-high current density of 100 A g-1 after 10000 cycles. The assembled lithium ion hybrid supercapacitors (LIHCs) also deliver a superior energy density of 50 Wh kg-1 at the ultra-high power density of 113 kW kg-1, really achieving both high energy density and power density of LIHCs. Therefore, the success of cable-like heterogeneous porous carbon architecture proposes a new direction of circumventing the discrepancy in kinetics and capacity mismatch, and also inspires more attentions on heterogeneous nanostructures with multifunction.