All-Climate Aluminum-Ion Batteries Based on Binder-Free MOF-Derived FeS₂@C/CNT Cathode

Aluminum-ion batteries (AIBs) are promising next-generation batteries systems because of their features of low cost and abundant aluminum resource. However, the inferior rate capacity and poor all-climate performance, especially the decayed capacity under low temperature, are still critical challenges toward high-specific-capacity AIBs. Herein, we report a binder-free and freestanding metal-organic framework-derived FeS₂@C/carbon nanotube (FeS₂@C/CNT) as a novel all-climate cathode in AIBs working under a wide temperature window between -25 and 50 °C with exceptional flexibility. The resultant cathode not only drastically suppresses the side reaction and volumetric expansion with high capacity and long-term stability but also greatly enhances the kinetic process in AIBs with remarkable rate capacity (above 151 mAh g^-1 at 2 A g^-1) at room temperature. More importantly, to break the bottleneck of the inherently low capacity in graphitic material-based all-climate AIBs, the new hierarchical conductive composite FeS₂@C/CNT highly promotes the all-climate performance and delivers as high as 117 mAh g^-1 capacity even under -25 °C. The well-designed metal sulfide electrode with remarkable performance paves a new way toward all-climate and flexible AIBs.