External Cooling and Degradation Interplay in Lithium-Ion Battery Fast Charging

Abstract

Fast charging of Li-ion batteries involves key challenges such as lithium plating, mechanical stress formation, high temperature rise, and non-uniform temperature distributions. The advancement of thermal management systems to maintain an optimal cell temperature distribution and minimize degradation is critical to enable fast charging. This work analyzes the various degradation modes, including lithium plating, solid electrolyte interphase growth, and mechanical stresses in large-format Li-ion cells during fast charging, and delineates their dependence on external cooling conditions. Based on the cell design and operating conditions, unique attributes related to the evolution of internal thermal gradients, spatiotemporal lithium plating response, and the formation of mechanical stress hotspots are delineated. Further, optimal external cooling configurations that enable longer life and safety under fast charging conditions are determined. The study provides guidance toward the design of next-generation battery thermal management systems for Li-ion batteries with fast charging capabilities.