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The corrosion mechanisms and kinetics of AA1085 in Li 2 SO 4 and LiNO 3 aqueous rechargeable lithium-ion battery electrolytes were investigated at pH 11 using chronoamperometry. The corrosion kinetics of AA1085 is controlled by the electrolyte concentration level and the anodic potentials. AA1085 is susceptible to crystallographic pitting corrosion in Li 2 SO 4 electrolytes. The rates of pit nucleation and pit growth both decreased at higher Li 2 SO 4 concentrations or at lower anodic potentials. AA1085 passivates against pitting corrosion in LiNO 3 electrolytes due to the formation of a thick, uniform corrosion product layer. The growth rate of the passive film was slightly enhanced by increasing the electrolyte concentration and anodic potentials. X-ray photoelectron spectroscopy spectra showed the formation of a thin sulfate-incorporated passive film on the electrode, which comprises Al 2 (SO) 4 18H 2 O, Al(OH)SO 4 and Al(OH) 3 , before the occurrence of pitting growth in 2 M Li 2 SO 4 electrolyte. The thick corrosion product layer formed in 5 M LiNO 3 electrolyte was composed of Al(OH) 3 and AlOOH. Raman spectroscopy on deionized water, LiOH solution, Li 2 SO 4 and LiNO 3 electrolytes depicted changes of solution structure with increasing electrolyte concentration. The influence of extrinsic and intrinsic factors on the corrosion kinetics of AA1085 in Li 2 SO 4 and LiNO 3 electrolytes at pH 11 are discussed in detail. [ABSTRACT FROM AUTHOR]

Aqueous rechargeable lithium-ion batteries (ARLBs) use aqueous electrolytes, which create conditions where corrosion may occur when aluminum is used as the current collector. The electrochemical stability of AA1085 in 2 M LiSO and 5 M LiNO aqueous electrolytes was evaluated over a range of pH conditions by cyclic voltammetry, linear sweep voltammetry, and chronoamperometry. Aluminum presented high corrosion resistance at pHs 5, 7, and 9 within the stability windows of both electrolytes. At the pH 11 condition, 2 M LiSO is capable of inhibiting aluminum from pitting but the inhibiting effect is not sustainable and crystallographic pitting occurs under a continuously applied anodic potential. Aluminum was well passivated against pitting in 5 M LiNO electrolyte at pH 11 due to the formation of a thick corrosion product barrier layer. Raman spectra depicted the presence of sulfate and nitrate anions on aluminum surface after cyclic voltammetry at pH 11. Inductively coupled plasma results showed that the amount of dissolved aluminum in electrolyte after cyclic voltammetry increases when pH increases from 5 to 11. The chemical adsorption mechanisms of sulfate and nitrate anions on aluminum were proposed to explain the dependency of electrochemical stability of aluminum on pH, anodic potential, and type of anions. The applicability of aluminum as current collector in ARLB using the 2 M LiSO and 5 M LiNO electrolytes is discussed. Graphical abstract: [ABSTRACT FROM AUTHOR]