Ultrafast and stable molten salt aluminum organic batteries

Aluminum-organic batteries (AIBs) have gained significant popularity for large-scale energy storage due to their abundance of aluminum reserves, cost-effectiveness, and environmental friendliness. However, the current aluminum-organic batteries primarily relied on ionic liquid electrolytes suffer from slow reaction kinetics and limited cycle life. Herein, we report a novel and efficient aluminum-organic battery that addresses these limitations by utilizing a molten salt electrolyte and designing a strongly interacting organic cathode. By enhancing π-π stacking interactions, we induced a transition in commercial PTCDA (Perylene-3,4,9,10-tetracarboxylic dianhydride) molecules from the β-phase to the highly interactive α-phase, known as PA450. This transformation not only stabilizes the structure of the PA450 electrode, preventing dissolution in the molten salt electrolyte, but also significantly improves electron conductivity. The Al||PA450 molten salt battery demonstrates exceptional electrochemical performance, exhibiting a high reversible capacity of 135 mAh g–1 and outstanding cyclability for up to 2000 cycles at 10 A g−1. Additionally, the structural rearrangement and ion transport properties induced by the co-intercalation of Al3+ and AlCl2+ were studied are investigated. This work provides deep insights into the unique characteristics of organic materials for ultrafast energy storage in molten salt electrolytes.