Mechanistic Understanding of Oxygen Electrodes in Rechargeable Multivalent Metal‐Oxygen Batteries

Abstract

Rechargeable multivalent metal‐O2 batteries (Mg−O2, Zn−O2 and Al−O2 etc.) are promising next‐generation battery technologies for electric automobiles and large‐scale energy storage owing to their high energy density, low cost, and sustainability. To realize the full potentials of these systems, an in‐depth mechanistic understanding of the underlying chemistries is crucial for rational development. However, compared with the intensively studied Li−O2 batteries, reaction mechanisms of multivalent metal‐O2 batteries are much less understood. Here, we discuss the current status of mechanistic understanding of oxygen reduction and evolution reactions in rechargeable multivalent metal‐O2 batteries. We discuss the key open questions and future research directions of multivalent metal‐O2 batteries using examples and experiences from Li−O2 batteries, which could guide and inspire the development of multivalent metal‐O2 batteries.

Advanced nano-bifunctional electrocatalysts in Li–air batteries for high coulombic efficiency

“…During discharge of the LAB (i.e., the oxygen reduction reaction, ORR), O 2 is reduced by Li ions to form Li ( per)oxides through the following reaction: 2Li 11,12 The discharge product LiO 2 can increase the theoretical specific energy; however, due to its electrochemical irreversibility, a large charge overpotential is incurred. 13,14 Thus, the formation of reversible Li 2 O 2 not irreversible LiO 2 is highly desirable for improving the performance and efficiency of LABs. Not to be overlooked is the fact that the specifics of the ORR can change with variations in the cathode and electrolyte surface states.…”

An air chargeable hydrogen battery by reversible electrochemical trapping of the protons

“…8,9 Though Li-ion batteries have revolutionized the portable electronic market for more than a decade, there are concerns related to the availability of raw materials and their cost. 4,7,[10][11][12][13] To overcome the growing energy demands, and the challenges associated with carbonbased energy economy and conventional energy storage technologies, a transition to a carbon-neutral energy economy is inevitable, which demands the development of environmentally friendly and affordable energy storage devices. [2][3][4][5][6][7][10][11][12][13][14][15][16][17] All of these mandate the focus on hydrogen economy, which refers to the use of dihydrogen as a fuel whose combustion in principle should be carbon neutral.…”

“…4,7,[10][11][12][13] To overcome the growing energy demands, and the challenges associated with carbonbased energy economy and conventional energy storage technologies, a transition to a carbon-neutral energy economy is inevitable, which demands the development of environmentally friendly and affordable energy storage devices. [2][3][4][5][6][7][10][11][12][13][14][15][16][17] All of these mandate the focus on hydrogen economy, which refers to the use of dihydrogen as a fuel whose combustion in principle should be carbon neutral. 5,18,19 Though this hydrogen-based energy economy by utilizing renewable and abundant energy sources is a promising energy vector, the temporal and geographic variations of renewable energy resources intro-duce a mismatch between the peak of its availability and the peak of its demand.…”

Corrosion engineering towards a high-energy Mn doped Co3O4 nanoflake cathode for rechargeable Zn-based batteries

“…Due to the inherent virtues of zinc (Zn) anodes and incombustible aqueous electrolytes, aqueous Zn-based batteries are receiving ever-increasing attention as a safe and economic alternative to lithium ion batteries and aluminium batteries. [1][2][3][4] The theoretical capacity of Zn is very high (B819 mA h g À1 ) with a low redox potential (À0.76 and -1.26 V versus standard hydrogen electrode (SHE) at pH = 7 and 14), which ensures its relative stability in aqueous solution. 5,6 Moreover, its reserves on earth are highly abundant and cheap for large-scale application.…”