Flexible Stable Solid‐State Al‐Ion Batteries

Abstract

Rechargeable aluminum-ion batteries (AIBs) are regarded as promising candidates for post-lithium energy storage systems (ESSs). For addressing the critical issues in the current liquid AIB systems, here a flexible solid-state AIB is established using a gel-polymer electrolyte for achieving robust electrodeelectrolyte interfaces. Different from utilization of solid-state systems for alleviating the safety issues and enhancing energy density in lithium-ion batteries, employment of polymeric electrolytes mainly focuses on addressing the essential problems in the liquid AIBs, including unstable internal interfaces induced by mechanical deformation and production of gases as well as unfavorable separators. Particularly, such gel electrolyte enables the solid-state AIBs to present an ultra-fast charge capability within 10 s at current density of 600 mA g −1 . Meanwhile, an impressive specific capacity ≈120 mA h g −1 is obtained at current density of 60 mA g −1 , approaching the theoretical limit of graphite-based AIBs. In addition to the well-retained electrochemical performance below the ice point, the solid-state AIBs also hold great stability and safety under various critical conditions. The results suggest that such new prototype of solid-state AIBs with robust electrode-electrolyte interfaces promises a novel strategy for fabricating stable and safe flexible ESSs.

Controllable Fabrication and Li Storage Kinetics of 1 D Spinel LiMn2O4 Positive Materials for Li‐ion Batteries: An Exploration of Critical Diameter

“…Figure a and b show the Nyquist plots of the as‐prepared product measured before cycling and after 500 cycles at room temperature, respectively. The semicircle in the high‐middle frequency region represents the Li diffusion across the surface film and the charge transfer reaction, whereas the inclined line in the low‐frequency region corresponds to the Warburg impedance ( Z w ) . The solution resistance ( R s ) and charge‐transfer resistance ( R ct ) were fitted by Zview software using the equivalent circuit shown in the inset of Figure a and the fitting results are listed in Table .…”

“…The semicircle in the high-middle frequency region represents the Li diffusion across the surfacef ilm andt he charge transfer reaction, whereas the inclinedl ine in the low-frequency region corresponds to the Warburg impedance (Z w ). [41][42][43] Thes olution resistance (R s )a nd charge-transfer resistance (R ct )w ere fitted by Zview software using the equivalent circuit shown in the inset of Figure 7a and the fitting resultsa re listed in Ta ble 2. It can be clearly seen that all of the four samples deliver similar R ct values before cycling.…”

A High Capacity Aluminum‐Ion Battery Based on Imidazole Hydrochloride Electrolyte

“…[8,9] Dai and co-workers presented a rechargeable Al-ion battery using costly [EMIm]Cl as electrolyte, which achieved a specific capacity of 60 mA h g À 1 . [10] Since then, more researchers have devoted themselves to the field of Al-ion batteries, positive electrode material, [11][12][13][14][15][16] current collector [17][18][19] and electrolyte. [20][21] The battery with urea as electrolyte yielded a specific capacity of 73 mA h g À 1 after 150 cycles.…”

Benzyltriethylammonium Chloride Electrolyte for High‐Performance Al‐Ion Batteries

“…These electrolytes significantly reduce the cost of AIBs system, and improved the capacity of batteries. Jiao's group prepared a flexible stable solid‐state AIB, and the battery with gel‐polymer as the electrolyte reached a specific capacity of 120 mA h g −1 at 60 mA g −1 . The battery with molten salt as the electrolyte required a harsh working environment, and the working temperature of AlCl 3 /LiCl/KCl inorganic molten salt was 120°C.…”

“…Jiao's group prepared a flexible stable solid-state AIB, and the battery with gel-polymer as the electrolyte reached a specific capacity of 120 mA h g À 1 at 60 mA g À 1 . [37] The battery with molten salt as the electrolyte required a harsh working environment, and the working temperature of AlCl 3 / LiCl/KCl inorganic molten salt was 120°C. Nann's group proposed a new electrolyte for rechargeable AIBs based on a room-temperature eutectic mixture of acetamide and AlCl 3 .…”