Due to the high volumetric capacity, low cost and high security, rechargeable aluminum batteries (RABs) become potential candidates for energy applications. However, the high charge density of Al³⁺ leads to strong coulombic interactions with anions and cathodes, resulting in slow kinetics diffusion and irreversible collapse of the cathode structure. Meanwhile, the commonly used electrolyte AlCl₃-based ionic liquids have serious corrosion on the battery components and are prone to side reactions. The above problems lead to low capacity and poor cycling stability. Here, the reduced graphene oxide (rGO) cathode with three-dimensional porous network was prepared by a simple and scalable method. The lamellar edges and oxygen-containing group defects of rGO synergistically provide abundant ion storage sites and enhance the kinetic. Matching with non-corrosive electrolyte 0.5 M Al(OTF)₃/[BMIM]OTF and Al metal, we constructed a high-performance battery, Al||rGO-150, with good cycling stability and discharge capacity of 80 mAh g⁻¹ after 3200 cycles. Quasi-in situ physicochemical characterization indicate that the ion storage mechanism is co-dominated by diffusion and capacitance. The capacity consists of the insertion of Al-based species cations as well as adsorption and insertion of OTF^- and [BMIM]⁺ synergistically. This work promotes the fundamental and applied research on RABs.

Sodium-ion batteries are considered as a promising low-cost alternative to commercial lithium-ion batteries. However, the harsh preparation conditions and unsatisfactory electrochemical performance of most sodium-ion batteries anode materials limit their commercial applications. Herein, we develop a new alloying/dealloying method for producing nano-scale tin from freezing point to room temperature. Due to the unique surface properties of tin particles, a tin/carbon composite with a compact structure is obtained. When coupled with a diglyme-based electrolyte, tin/carbon composite (contains 60 wt.% tin) exhibits a reversible capacity of 334.8 mAh·g⁻¹ after 1,000 cycles at 500 mA·g⁻¹. An as-prepared tin/carbon anode||high-load vanadium phosphate sodium full cell (N/P ratio: 1.07) shows a stable cycle life of 300 cycles at 1 A·g⁻¹. The achievement of such an excellent performance can be ascribed to the carbon conductive network and robust solid electrolyte interphase film, which facilitates the fast transportation of electrons and Na ions. This work provides a new idea to prepare other alloyed anode materials for high-performance sodium-ion batteries.