OER Mechanism Development and Optimization of the Air Electrode for Lithium-Air Batteries
Lithium-air batteries use a new battery chemistry that has a theoretical energy density 4-6 times higher than conventional lithium-ion batteries. This dramatic increase in energy density will enable a new generation of electric vehicles and portable devices with greater range and lower weights. These batteries operate by reacting metallic lithium with oxygen from the atmosphere, forming solid lithium peroxide within the air electrode of the battery. Several significant obstacles remain that prevent practical application of lithium-air batteries. One is the significant overpotential required to recharge the battery (the oxygen evolution reaction, or OER), which has been reported as high as 1.5 V. As the equilibrium potential is only 2.9 V, more than 50% extra energy is wasted during such recharge cycles. Several catalysts have been shown to reduce this overpotential, but the reaction is poorly understood, as is the manner in which these catalysts reduce overpotential.
Thesis aims are:
Aim 1: Develop a methodology of quantitatively determining OER activity, and examine that activity across a variety of catalysts.
Aim 2: Develop a proposed reaction mechanism for OER of in lithium air batteries.
Aim 3: Construct an air-electrode that optimizes power and energy density while improving OER efficiency.