Binder-Free V2O5 Cathode for High Energy Density Rechargeable Aluminum-Ion Batteries

Abstract

Nowadays, research on electrochemical storage systems moves into the direction of post-lithium-ion batteries, such as aluminum-ion batteries, and the exploration of suitable materials for such batteries. Vanadium pentoxide (V2O5) is one of the most promising host materials for the intercalation of multivalent ions. Here, we report on the fabrication of a binder-free and self-supporting V2O5 micrometer-thick paper-like electrode material and its use as the cathode for rechargeable aluminum-ion batteries. The electrical conductivity of the cathode was significantly improved by a novel in-situ and self-limiting copper migration approach into the V2O5 structure. This process takes advantage of the dissolution of Cu by the ionic liquid-based electrolyte, as well as the presence of two different accommodation sites in the nanostructured V2O5 available for aluminum-ions and the migrated Cu. Furthermore, the advanced nanostructured cathode delivered a specific discharge capacity of up to ~170 mAh g−1 and the reversible intercalation of Al3+ for more than 500 cycles with a high Coulomb efficiency reaching nearly 100%. The binder-free concept results in an energy density of 74 Wh kg−1, which shows improved energy density in comparison to the so far published V2O5-based cathodes. Our results provide valuable insights for the future design and development of novel binder-free and self-supporting electrodes for rechargeable multivalent metal-ion batteries associating a high energy density, cycling stability, safety and low cost.

Recent Progress and Challenges in Multivalent Metal‐Ion Hybrid Capacitors

“…Other battery‐type materials used in AIBs, such as transition metal oxygen/sulfide TiO 2 , [77] V 2 O 5 , [12d] Mo 6 S 8 , [78] MoS 2 [79] and WS 2 microchips, [80] can be considered as battery‐type electrodes of AHC devices.…”

Cation-intercalation and conversion-type cathode materials for rechargeable aluminum batteries

“…26 Nevertheless, a number of studies of V 2 O 5 as the RAB cathode material have been reported since. 9,10,12,[25][26][27][28] Gu et al attempted to elucidate the intercalation mechanism and the phase transformation induced by Al 3+ in V 2 O 5 . 10 The galvanostatic discharge-charge curves in their study show a stable discharge slope at 0.6 V and a charge slope around 1.0 V versus Al as displayed in Fig.…”

“…A Li 3 VO 4 @C composite was demonstrated as a cathode material for RABs with an initial capacity of 137 mA h g À1 at a current density of 20 mA g À1 . 11 Ex situ XRD, XPS, 27 Al nuclear magnetic resonance (NMR), and first-principles calculations were applied to study the Al 3+ intercalation mechanism in Li 3 VO 4 . The discharge-charge curves and cyclic voltammogram (CV) clearly indicated redox reactions despite lower coulombic efficiency (CE) in the first cycle.…”

Synthesis of naked vanadium pentoxide nanoparticles

“…V 2 O 5 is also suitable in electrochemical applications. 7,8 Indeed, V 2 O 5 has been extensively studied as electrode materials in lithium-ion batteries (LIBs), [9][10][11] in aluminum-ion batteries (AIBs), 12 zinc-ion batteries (ZIBs) 13,14 and in supercapacitors 15,16 due to its unique crystalline structure. It is also used as a nano-powder in latent nger print detection (LFPD).…”