Anti-pulverization intermetallic Fe–Sn anchored on N-doped carbon anode boosted superior power and stable lithium storage

Abstract

Tin (Sn) anode suffers from considerable volume deformation, generating vast dilatation-induced stresses leading to pulverization for lithium-ion batteries (LIBs). Herein, the Sn–Fe–C composite anode material with a jujube cake-like structure where Sn/FeSn2 metalcore anchored on an N-doped carbon matrix is constructed. During the lithiation process, the intermetallic Fe–Sn (FeSn2) generates Fe nanoparticles, which are uniformly distributed in the Sn matrix to relieve internal stress and create a conductive network, thus enhancing electron conduction and ion diffusion kinetics. In addition, the N-doped carbon matrix maintains the material structural integrity and improves overall conductivity. Consequently, the Sn–Fe–C anode delivers a high reversible 400 mAh g−1 over 1100 cycles at 5 A g−1 (capacity retention of up to 90.9%) and rate performance (237 mAh g−1 at 20 A g−1). Sn–Fe–C anode pairs with porous carbon (PC) cathode to assemble lithium-ion capacitors (Sn–Fe–C || PC LICs), which show a maximum energy density of 203.8 Wh kg−1, an excellent power density of 23925.3 W kg−1, and energy retention rate of 72.9% after 18,000 cycles at 1 A g−1. The Sn–Fe–C material as an anti-pulverization anode could be a potential application for high-performance LIBs and LICs in the future.