Tin Sulfide-Based Nanohybrid for High-Performance Anode of Sodium-Ion Batteries

Nanohybrid anode materials for Na-ion batteries (NIBs) based on conversion and/or alloying reactions can provide significantly improved energy and power characteristics, while suffering from low Coulombic efficiency and unfavorable voltage properties. An NIB paper-type nanohybrid anode (PNA) based on tin sulfide nanoparticles and acid-treated multiwalled carbon nanotubes is reported. In 1 m NaPF₆ dissolved in diethylene glycol dimethyl ether as an electrolyte, the above PNA shows a high reversible capacity of ≈1200 mAh g⁻¹ and a large voltage plateau corresponding to a capacity of ≈550 mAh g⁻¹ in the low-voltage region of ≈0.1 V versus Na⁺/Na, exhibiting high rate capabilities at a current rate of 1 A g⁻¹ and good cycling performance over 250 cycles. In addition, the PNA exhibits a high first Coulombic efficiency of ≈90%, achieving values above 99% during subsequent cycles. Furthermore, the feasibility of PNA usage is demonstrated by full-cell tests with a reported cathode, which results in high specific energy and power values of ≈256 Wh kg⁻¹ and 471 W kg⁻¹, respectively, with stable cycling.