Formation of solid‐solution Co _x Ni _{1− x} CO ₃ as high‐performance anode materials for lithium‐ion batteries

Abstract

Transition metal carbonates (TMCs) as high-performance anode materials for lithium-ion batteries (LIBs) have attracted intensive research interests in recent years. Nanostructures with abundant pore channels can well address the volume change during the Li + insertion/desertion process and shorten the ionic diffusion length. Multi-component carbonates with excellent porous structures exhibit enhanced electrochemical performance in contrast to the mono-component carbonates due to the synergistic effect among multi-metal elements. Herein, we used a simple solvothermal method to synthesize Cobased solid-solution carbonates Co x Ni 1Àx CO 3 to obtain different microstructures by changing the content of the precipitant. The optimized solid-solution Co 2/3 Ni 1/3 CO 3 (CNCO-20) delivers a high initial Coulombic efficiency of 83%,a reversible high-rate capacity of 828.1 mAh g À1 at 2.0 A g À1 , and good electrochemical stability with a reversible capacity of 740.9 mAh g À1 after 500 chargedischarge cycles at 1.0 A g À1 due to the enhanced electronic/ionic transport, sufficient electroactive sites, and improved electrochemical stabilities. Considering the excellent specific capacity and long life-span, the synthesized solidsolution CNCO-20 demonstrate great promise as an alternative anode electrode material compared to conventional materials for LIBs. K E Y W O R D S lithium-ion batteries, multi-component carbonates, solid-solution Co x Ni 1Àx CO 3 , solvothermal method, transition metal carbonates