Synthesis and Electrochemical Properties of Amorphous Carbon Coated Sn Anode Material for Lithium Ion Batteries and Sodium Ion Batteries

Abstract

Sn is one of the promising anode material for lithium-ion and sodium-ion batteries because of Sn has many advantages such as a high theoretical capacity of 994 mAh/g, inexpensive, abundant and nontoxic. However, Sn-based anodes have a critical problem from pulverization of the particles due to large volume change (>300% in lithium-ion battery and 420% in the sodium-ion battery) during alloying/dealloying reaction. To overcome this problem, we fabricate Sn/C particle of core/shell structure. Sn powder was produced by pulsed wire explosion in liquid media, and amorphous carbon coating process was prepared by hydrothermal synthesis. The charge capacity of Sn electrode and amorphous carbon coated Sn electrode was 413 mAh/g and 452 mAh/g after 40 cycles in lithium half-cell test. The charge capacity of Sn electrode and amorphous carbon coated Sn electrode was 240 mAh/g and 487 mAh/g after 40 cycles in sodium half-cell test. Amorphous carbon coating contributed to the improvement of capacity in lithium and sodium battery systems. And the effect of amorphous carbon coating in sodium battery system was superior to that in lithium battery system.