A Non-Flammable Flexible Aluminum-Lithium Dual-Ion Battery with a Wide Temperature Range Based on Ionic Liquid Electrolytes

Abstract With the rapid development and increase in popularity of electric vehicles and wearable devices, battery safety in the field of energy storage has become an increasingly strong focus. Aluminum-ion batteries (AIBs) are gaining attention as energy-storage systems that are low cost with high levels of safety and high theoretical energy density. However, to date, the dense alumina passivation layer on the aluminum anode surface and the slow kinetic performance of the IL (ionic liquid) electrolyte has rendered their performance unsatisfactory. We have reported on a new type of lithium–aluminum battery that maintains a certain discharge performance under destructive conditions such as continuous bending, high- and low-temperature environments, and shearing. The prepared AlLi metal battery achieved a stable cycle of 130 mAh g − 1 specific capacity and approximately 260 Wh kg − 1 energy density at a wide voltage platform of 2 V and a test temperature of 25°C. The batteries did not experience combustion and this product can meet the current demand for flexible and safe batteries. We also analyzed the reaction mechanism and principle of this Al–Li cell based on density functional theory and conducted ex situ XRD and XPS tests to elucidate the storage mechanisms of the Al-Li battery.