The molten chlorides for aluminum-graphite rechargeable batteries

A low-cost, high-capacity Al-graphite rechargeable aluminum-ion battery is confirmed to be able to work stably in a quaternary AlCl3-NaCl-LiCl-KCl inorganic molten salt as electrolyte with the lowest eutectic temperature of less than 75 degrees C. The battery shows a stable specific capacity of 114.9 mAh g(-1) at 200 mA g(-1) over 1500 cycles at 90 degrees C. Moreover, the capacity can remain at similar to 85 mAh g(-1) with a higher current density of 800 mA g(-1) over 2600 cycles at 90 degrees C. Importantly, even cycled at 80 degrees C and 100 degrees C, almost 100% capacity retention can be achieved after 5800 cycles when the temperature is back to 90 degrees C, verifying the superior long-term cycling stability under various temperatures. The inherent low-cost and high capacity, as well as outstanding long-term cycling stability, makes it particularly favorable for large-scale energy storage devices. (C) 2019 Elsevier B.V. All rights reserved.