Harrison's Electrochimica Acta Paper Published
A study borne from my PhD work investigates the effects of mass transport and its interplay with electrochemical kinetics for aluminium-organic batteries. The study purports that there are two competing mechanisms in aluminum-quinone batteries, one that exists under high flux of intercalants, and the other under low flux. The mechanisms are dubbed concurrent and sequential, with these names relating to the ordering of the two-step electronic reduction and corresponding charge compensation. The concurrent mechanism occurs when the electrochemical Damköhler number is small (e.g., under high flux or low rates), and is ordered as electronic reduction-complexation-electronic reduction-complexation; the sequential mechanism by comparison occurs under conditions where the Damköhler number is large, and is ordered electronic reduction-electronic reduction-complexation-complexation. The key difference is that the uncompensated semiquinone form (after the first electronic reduction) is reduced at lower discharge potentials than the ionically compensated semiquinone. These mechanisms can be considered like putting on socks and shoes, you can go sock-shoe-sock-shoe (concurrent, small Dael), or sock-sock-shoe-shoe (sequential, large Dael). This study has consequences to any multielectronic organic electrodes, and tests multiple methods to affect Dael, all to the same conclusion.