Mechanistic Interrogation of Thermal Gradients and Crosstalk in Solid-State Batteries
Abstract
Solid-state batteries (SSBs) present a tantalizing landscape for electrochemical energy storage and have garnered tremendous research attention in recent years. The development of SSBs, which replace the liquid electrode and graphite anode in Li-ion batteries with a solid electrolyte (SE) and Li metal, holds tremendous potential to offer superior energy density and safety. The utilization of inorganic SEs in SSBs, due to their intrinsic mechanical rigidity and nonflammability, is considered an important step towards mitigating dendrite growth and enabling Li metal anodes. In addition, the recent discovery and development of single-ion conductors has demonstrated ionic conductivities close to several liquid electrolytes. The absence of ionic concentration gradients in such single-ion conductors can theoretically alleviate major fast-charging challenges associated with liquid electrolytes. Despite the exciting promise, the development of practical SSBs is confronted with various challenges such as filament growth, mechanical failure of the SE, void formation and interphase evolution. Filamentous Li exhibiting a wide range of morphologies has been observed to penetrate several SE systems, resulting in an internal short-circuit. The propensity of this failure mechanism is controlled by various aspects including the SE microstructure, presence of defects and surface heterogeneities, mechanical and transport properties of the SE and Li, and operating conditions such as external pressure. Analogous to plating, the rate performance of SSBs during stripping is restricted by the dynamic evolution of interfacial voids. While understanding such chemo-mechanical limitations has been a pivotal focus of recent research, the mechanistic underpinnings of thermal interactions in SSBs still require critical interrogation.With an intrinsic boost in energy densities, SSBs can involve a substantial thermal response, warranting a detailed scale-bridging analysis including electrode-scaleto cell-format implications. The manifestation of thermal inhomogeneities can affect various responses includingthe active material utilization, transport interactions in the solid-state cathode and void growth behavior at the anode-SE interface. For instance, the self-heat generated in the cathode alters the efficacy of ionic percolation and reaction current homogeneity in the cathode. Reaction heterogeneities during plating can potentially result in thermal hotspots, exacerbating the local propensityfor filament propagation and interphase formation. Through this project, we will understand the fundamental correlation between thespatio-temporal heterogeneity in thermal response within the solid-state cell sandwich and the resulting performance and degradation attributes. As SSBs are expected to meet a variety of electromobility needs such as fast charging and low-temperature operation, understanding the underlying thermo-electrochemical interactions is of paramount importance. We will develop a hierarchical modeling framework capturing the thermally-coupled processes ranging from the electrode-scale to cell-format. Various mechanistic interactions in SSBs including the manifestation of thermal gradients across the cell sandwich, thermo-electrochemical coupling at solid-solid interfaces, origin of spatio-temporal heterogeneities, electrode crosstalk and resulting degradation signatures (e.g., void formation) will be investigated in this research effort.Approved for Public Release, Dr. Partha Mukherjee 03/10/2023
Document Details
- Document Type
- DoD Grant Award
- Publication Date
- Jul 24, 2023
- Source ID
- N000142312608
Entities
People
- Partha P. Mukherjee
Organizations
- Office of Naval Research
- Purdue University
- United States Navy