Novel Electrospun Sn-Based Composite Cathodes Exhibiting Extended Cycle Life for Hybrid Magnesium-Lithium Batteries

In this study, we present a strategic approach for the structural design and composite modification of one-dimensional Sn-based nanocomposites to enhance the overall electrochemical performance of hybrid magnesium-lithium batteries (MLIBs), which are emerging as promising successors to lithium-ion batteries. By using electrospinning technology, we successfully synthesized NST-SnO₂, NST-SnO₂-NiO, Sn-CNF, and Ni₃Sn₂-CNF composite cathodes, as well as analyzed the synthesis mechanism of the four Sn-based cathodes. The 100-cycle testing at a current density of 500 mA·g^-1 revealed that NST-SnO₂ maintained a discharge specific capacity of 129.8 mA h·g^-1 with a retention rate of 90.76%, while NST-SnO₂-NiO achieved a higher capacity of 147.4 mA h·g^-1 and an 88.05% retention rate. Notably, Sn-CNF and Ni₃Sn₂-CNF exhibited initial discharge capacities of 66.7 and 79.6 mA h·g^-1, respectively, coupled with exceptional cycle stability, evidenced by retention rates of 104.19 and 102.38%. The remarkable cycling stability observed in these novel cathodes is attributed to their robust structural integrity, thus demonstrating the potential for an extended cycle life in MLIBs. This work provides significant advancement in the development of high-performance electrode materials for next-generation hybrid magnesium-lithium energy storage systems.