Design of workflows for crosstalk detection and lifetime deviation onset in Li-ion batteries

Abstract

<h2>Summary</h2> Developing advanced electrolytes or electrode materials for Li-ion batteries heavily relies on the use of performance metrics, among which capacity retention and Coulombic efficiency remain the gold standards. While powerful at predicting initial degradation rates, these metrics fall short of predicting knee points that can abruptly lead to the sudden death of battery cells. Indeed, knee points often originate from complex interplays between electrodes, through a cascade of parasitic reactions or the modification of the cell balancing. In this work, we analyze and demonstrate how combining adequate electrochemical testing protocols, coupled with advanced electrochemical analysis, allows for disentangling effects as complex as the crosstalking events for selected graphite Ni-rich cell chemistries. We believe that, using this set of workflows, a comprehensive analysis of capacity retention curves can be accurately carried out. This approach should become the new standard for screening novel electrolytes and materials for high-performance battery chemistries.