Understanding the Atomic to Mesoscale Gap in Li-Ion Battery Failure with Reactive Coarse-Graining Methodologies
Abstract
Understanding the Atomic to Mesoscale Gap in Li-Ion Battery Failure with Reactive Coarse-Graining MethodologiesBrett M. SavoieChemical Engineering, Purdue UniversityBudget: $501,208The maturation of Li-ion battery technology has played a critical enabling role inmanifold applications that are crucial to the Navy, including portable electronics, robotics, and propulsion. Despite these successes, the stability of Li-ion batteries is still inadequate for many applications and our current understanding of battery failure is largely driven by empirical post mortem analysis. Decades of experience with Li-ion batteries has shown that subtle changes in electrolyte composition can dramatically impact stability through the formation of passivation layers known as the solid-electrolyte interphase (SEI) at the electrodes. The SEI is composed of degradation products of the electrolyte that is ideally electronically insulting but ionically conductive. SEI breakdown plays a critical role in mediating failure modes in Li-ion batteries, with desirable behaviors ranging from gradual capacity loss that can be externally monitored and proactively addressed, to undesirable behaviors ranging from internal short circuit, thermal runaway, and gas generation, depending on SEI details. Although extensive theoretical studies have been conducted on the initial stages of SEI formation, the chemical processes occurring in the SEI leading up to catastrophicfailure have scarcely been modeled and are difficult to experimentally observe in situ. This knowledge gap, in turn, frustrates predictive modeling of catastrophic failure at the mesoscale and device scales, and ultimately inhibits the development of safe batteries. To make further progress in understanding Li-ion battery failure, as well as bringing post Li-ion batteries to viability, thus requires the development of modeling methodologies that link molecular scale SEI processes that accompany and precede catastrophic failure with larger length and timescale modeling that has matured over the past decade. Here we propose to address this gap using reactive coarse-grained models that support the simulation of the diverse reaction chemistries that are typical of SEI evolution and breakdown. To accomplish this, we will develop and implement a hybrid Kinetic Monte Carlo and Molecular Dynamics (KMC/MD) method to address longer lengthscales and timescales than have been achievable to date while incorporating accurate kinetics for the competing processes that accompany SEI-mediated battery failure. The timing for this approach is supported by recent developments by our group for elucidating chemical network kinetics, which provides an avenue for connecting quantum chemical derived kinetics with coarse-grained simulation scales that has yet to occur in the context of battery failure modeling. The specific goals in this project are: (1)fracture; (3) Establishing a molecular-based description of local mobility, thermal transport, and mass transport in the SEI that can be utilized in larger-lengthscale mesoscale modeling and experimental characterization efforts. Successful completion of these goals will address the knowledge gap between atomistic and mesoscale modeling menological to the realm of the predictive. These capabilities will thus advance Naval battery research in several positive ways, including by aiding the design of safer battery configurations, facilitating experimental design and interpretation of battery failure modes, and also providing descriptions of interfacial electrochemistry in adjacent applications of relevance to the Navy. Approvedfor Public Release
Document Details
- Document Type
- DoD Grant Award
- Publication Date
- Aug 05, 2021
- Source ID
- N000142112647
Entities
People
- Brett Savoie
Organizations
- Office of Naval Research
- Purdue University
- United States Navy