High-Quality Graphene Microflower Design for High-Performance Li-S and Al-Ion Batteries

Poor quality and insufficient productivity are two main obstacles for the practical application of graphene in electrochemical energy storage. Here, highquality crumpled graphene microflower (GmF) for high-performance electrodes is designed. The GmF possesses four advantages simultaneously: highly crystallized defect-free graphene layers, low stacking degree, sub-millimeter continuous surface, and large productivity with low cost. When utilized as carbon host for sulfur cathode, the GmF-sulfur hybrid delivers decent areal capacities of 5.2 mAh cm(-2) at 0.1 C and 3.8 mAh cm(-2) at 0.5 C. When utilized as cathode of Al-ion battery, the GmF affords a high capacity of 100 mAh g(-1) with 100% capacity retention after 5000 cycles and excellent rate capability from 0.1 to 20 A g(-1). This facile and large-scale producible GmF represents a meaningful high-quality graphene powder for practical energy storage technology. Meanwhile, this unique high-quality graphene design provides an effective route to improve electrochemical properties of graphene-based electrodes.