Novel One-Dimensional Nanofiber MnSe/CMK-3 High-Performance Cathode Material for Aluminum Batteries

Transition metal selenides have shown outstanding performance as cathode materials for aluminum-ion batteries and have thus become a popular choice for cathode materials. Herein, Mn-based carbon fibers (Mn/CNFs) were first synthesized by electrospinning as a precursor, and then MnSe composites were prepared by a melt-diffusion method. However, due to polyselenides and selenides being generated during electrochemical reactions, the cycling stability of MnSe cathode materials is poor. After 200 cycles, the discharge specific capacity is only 176 mA h/g. To suppress the shuttle effect of selenides and polyselenides, a CMK-3-modified separator was used instead of a glass fiber separator. Compared with MnSe-800, the replaced MnSe-800/CMK-3 has a great capacity improvement; the initial discharge specific capacity is 1029.85 mA h/g, which after 3000 cycles, still remains at 297.84 mA h/g. The soft pack battery can still light up the LED normally under different degrees of folding, which proves the application of this material in wearable devices. This work provides a new way to improve the performance of transition metal selenides.