Synergistic co-embedding of metal ions and hydrogen protons for high stability double salt aqueous aluminum battery

Abstract

As a favorable competitor of the next generation for large-scale energy storage components, aluminum batteries (ABs) have received attention from all walks of life. However, the air sensitivity and corrosiveness of non-aqueous electrolytes seriously hinder the further development of aluminum ion batteries (AIBs). ABs meet the needs of green development and become a key research object. An excellent performance is reflected in the energy storage system of Al/4 M Al(OTF)3+1M Ca(OTF)2(4Al+Ca)/AlxMnO2·nH2O. It has an excellent discharge platform of 1.5 V, and can still maintain a high specific capacity of 233 mAh/g after 100 cycles. The co-intercalation of metal ions and protons has been demonstrated by EELS and SSNMR. What is most interesting is that during discharging, Ca2+ has the dual function of balancing charge and supporting material. MnO undergoes in-situ electrochemical conversion during charging and combines with Al3+ to form AlxMnO2·nH2O. In addition, the elaboration of the ion diffusion and solvation strategies inside the double-salt electrolyte is also an important exploration for the further development of aqueous aluminum batteries (AABs).