Oxygen vacancies enriched Bi2O3 as high capacity and high rate negative material for aqueous alkali battery

Abstract

Aqueous alkaline batteries (AABs) represent a prospective category of rechargeable energy devices that can ensure both high energy and power densities. The high capacity negative material is urgently needed to match with the positive electrode and maximize the overall charge storage ability of AAB. Herein, an oxygen vacancies (Ov) enriched Bi2O3 was prepared as efficient negative material for AAB via solvothermal hydrolysis of Bi salt and calcination in inert atmosphere. The resultant Bi2O3 electrode demonstrated high specific capacity (Cs) of 249 mAh g−1 at 1 A g−1 and ultrahigh rate capability (230 mAh g−1 at 10 A g−1) in a wide negative potential range, which was higher than those of other battery materials. When paired with Co, Ni layered double hydroxide (CoNi-LDH) positive electrode, the AAB based on the Bi2O3 negative electrode delivered high energy density (Ecell, 87.1 Wh kg−1 at power density (Pcell) of 1037 W kg−1) and good durability, manifesting the potential of Ov enriched Bi2O3 in battery typed charge storage.