Constriction Percolation Model for Coupled Diffusion-Reaction Corrosion of Zirconium in PWR

We develop a new constriction-based percolation paradigm, using cellular automata to predict the transport of oxygen through a stochastically-cracked Zr oxide layer within a real-time coupled diffusion-reaction framework We simulate such branching trees by generating a series of porosity-controlled media. Furthermore, we develop an analytical criterion based on compressive yielding for bridging the transition state in corrosion regime, where the percolation threshold has been achieved. Consequently, our model predicts the arrival rate of oxygen ions at the oxide interface during the so-called post-transition regime, where the bulk diffusion is no longer the rate-limiting factor

Lithium Dendrite Growth Control Using Local Temperature Variation

We have quantified lithium dendrite growth in an optically accessible symmetric Li-metal cell, charged under imposed temperatures on the electrode surface. We have found that the dendrite length measure is reduced up to 43% upon increasing anodic temperature of about 50°C. We have deduced that imposing higher temperature on the electrode surface will augment the reduction rate relative to dendritic peaks and therefore lithium holes can draw near with the sharp deposited tips. We have addressed this mechanism via fundamentals of electrochemical transport

Quantifying the dependence of dead lithium losses on the cycling period in lithium metal batteries

We quantify the effects of the duration of the charge–discharge cycling period on the irreversible loss of anode material in rechargeable lithium metal batteries. We have developed a unique quantification method for the amount of dead lithium crystals (DLCs) produced by sequences of galvanostatic charge–discharge periods of variable duration τ in a coin battery of novel design. We found that the cumulative amount of dead lithium lost after 144 Coulombs circulated through the battery decreases sevenfold as τ shortens from 16 to 2 hours. We ascribe this outcome to the faster electrodissolution of the thinner dendrite necks formed in the later stages of long charging periods. This phenomenon is associated with the increased inaccessibility of the inner voids of the peripheral, late generation dendritic structures to incoming Li+