Sandwich Structure Electrode as Advanced Performance Anode for Lithium-Ion Batteries

Abstract

In this work, a sandwich structure electrode was prepared by a simple vacuum filtration and rolling process. The SEM showed that the active materials were uniformly embedded in the pores of the three-dimensional conductive network of the carbon nanotube (CNTs) conductive paper. The contact interface area of active material and the conductive network significantly increased and the interface resistance was greatly reduced. The porous anode can accommodate the volume expansion of the silicon and effectively alleviated pressed during cycle. The electrode also exhibited good stability in cycles. Electrochemical tests showed that the first discharge specific capacity of the sandwich electrode reached 2330[Formula: see text]mAh/g with a coulombic efficiency of 86%. After 500 cycles, the specific capacity was still maintained at 1512[Formula: see text]mAh/g. At a large current density of 2[Formula: see text]A/g, the specific capacity hold was 840[Formula: see text]mAh/g compared with the copper foil electrode of 100[Formula: see text]mAh/g.