ALUMINUM-ETHER-BASED COMPOSITION FOR BATTERIES AND AMBIENT TEMPERATURE ALUMINUM DEPOSITION (iEdison No. 0685901-22-0051)

Patent ID: 10640 | Status: Filed

Abstract

We invented and demonstrated a novel electrolyte formulation comprised of dialkyl ethers (R1-O-R2, R: hydrocarbon functional groups) and aluminum chloride (AlCl3) that enables efficient, room-temperature electrochemical reduction of Al3+ to metallic aluminum (i.e., electrodeposition) and highly reversible oxidative stripping of metal to Al3+ ions (i.e., galvanic dissolution). The chemical formula of our electrolyte solution can be represented by nAlCl3 : mR1-O-R2 (0.1 ≤ m/n ≤ 5). The dialkyl ether (R1-O-R2) systems include widely available industrial solvents such as dipropyl ether (DPE) and dibutyl ether (DBE). At room temperature (~20 ºC) mixing of DPE or DBE (Lewis base) with AlCl3 (Lewis acid) forms yellowish solutions with high concentrations of Al3+ (up to 7.3 M). This unique electrolyte formulation enables highly efficient and reversible electrochemical processes (both electrodeposition and dissolution) and hence can be considered as a potential candidate for (i) high temperature Al coating in industrial processes, (ii) rechargeable aluminum-based batteries. Our novel electrolyte formulation is based on improving the rates of desolvation and resolvation steps during electrochemical processes by suppressing electrostatic interactions of multivalent Al3+ ions via weakly coordinating ethereal based solvents. The DPE/AlCl3 and DBE/AlCl3 electrolyte solutions demonstrate highly reversible Al plating/stripping at room temperature with low overpotential of - 0.2 V vs. Al/Al3+(Figure 1). The electrochemical performance of dialkyl ether-based electrolytes is more efficient and reversible compared to widely used electrolyte systems, such as ionic liquid based solvents reported in literature. Figure 1. Cyclic voltammograms of Pt electrode with the electrolyte solution of (A) AlCl3:DPE and (B) AlCl3:DBE at 1:1.2 (molar ratio) at 0.25 mV s-1 between - 0.8 - 1.5 V vs Al/Al3+. Highly efficient Al plating and stripping behavior is observed.

Application Number

18/130,281

Inventors

Nguyen,Dan Thien
Mueller,Karl T
Prabhakaran,Venky
Murugesan,Vijay

Market Sector

Materials
Chemistry and Catalysts