Copper and Cobalt Nanoparticles Enable Highly Stable and Fast Kinetics of Al–S Batteries

Abstract

Aluminum–Sulfur (Al–S) batteries are regarded as promising energy storage devices due to their high energy‐to‐price ratios and safety. However, they suffer from clumsy S ↔ Al2S3 reactions and short lifespans that limit their practical application. By combining the merits of adsorptive Cu, catalytic Co, and conductive N‐doped carbon matrix, the bimetals decorated N‐doped carbon (Cu1Co1@NC) enables smooth adsorption and conversion of polysulfides. Consequently, the S@Cu1Co1@NC exhibits excellent electrochemical performance (delivering a high capacity of 317.5 mAh g−1 after 320 cycles at 1.5 A g−1). Moreover, the Cu‐endowed strong Al affinity and robust 3D scaffold with Co‐enhanced conductivity can regulate Al3+ depositing/stripping and successfully suppress Al dendrites. As a result, the Cu1Co1@NC displays negligible Al nucleation overpotential and provides ultra‐long lifespan (>10 000 h) and exceptional reversible (Coulombic efficiency = 99.8–99.9%) Al3+ plating/stripping. Integrating all these advantages, a full Al–S cell constructed with Cu1Co1@NC as two‐in‐one hosts demonstrates excellent capacity retention with enhanced reversibility. This work provides insights into the design of promising Al–S batteries based on bifunctional CuCo bimetal and favorable 3D framework.

Locally Concentrated Deep Eutectic Liquids Electrolytes for Low‐Polarization Aluminum Metal Batteries

“…[ 7,8 ] Due to the capability of reversible aluminum stripping/plating at room temperature via the conversion between AlCl 4 − and Al 2 Cl 7 − (Equation ()), this electrolyte has been widely used realizing high‐performance AMBs with various different cathode materials, such as graphite, [ 9–11 ] transition metal chalcogenides, [ 12–16 ] Prussian blue analogues, [ 17 ] MXenes, [ 7,18–20 ] organic compounds, [ 21,22 ] and chalcogens. [ 23–27 ] However, the high cost of [EMIm]Cl greatly limits the development of AMBs. [ 28 ] To tackle the cost factor, deep eutectic liquid electrolytes (DELEs) formed via mixing of the Lewis acid AlCl 3 with a Lewis basic ligand like urea were proposed as alternative electrolytes, [ 29 ] in which the heterolytic cleavage of AlCl 3 leads to the generation of AlCl 4 − , Al 2 Cl 7 − , and [AlCl 2 ·(ligand) n ] + .…”