Stable quasi-solid-state Aluminum Batteries.

Nonaqueous rechargeable aluminum batteries (RABs) of low cost and high safety are promising for next-generation energy storage. With the presence of ionic liquid (IL) electrolytes, their high moisture-sensitivity and poor stability would lead to critical issues in the liquid RABs, including undesirable gas production, irreversible activity loss and unstable electrode interface, which undermines the operation stability. To address such issues, herein a stable quasi-solid-state electrolyte is developed via encapsulating a small amount of IL into a metal organic framework (IL@MOF), which not only prevents IL from moisture, but creates sufficient ionic transport network between active materials and electrolyte. Owing to the generated stable states at both positive electrode-electrolyte and negative electrode-electrolyte interfaces, the as-assembled quasi-solid-state Al-graphite batteries deliver specific capacity of ∼75 mA h g-1 (with positive electrode material loading ∼9 mg cm-2 , much higher than that in the conventional liquid systems). The batteries present a long-term cycling stability beyond 2000 cycles, with great stability even upon exposing to air within 2 hours and under flame combustion tests. Such technology opens a new platform of designing highly safe rechargeable Al batteries for stable energy storage. This article is protected by copyright. All rights reserved.