Diagnostic Identification of Reversible Lithium Stripping Kinetics under Cold Operation
Reversible lithium stripping under cold operation requires voltage relaxation or dQ/dV diagnostic tracking to adjust BMS derating and protect cycle life.
Reversible Stripping
Meaning
Electrochemical dissolution reaction removes deposited metallic lithium from a substrate back into electrolyte ions during cell discharge without forming dead metal or structural moss. Next-generation lithium metal and anode-free cell architectures depend on efficient metal oxidation to achieve high energy density and long cycle life. Through optimized liquid or solid electrolyte interfaces, reversible stripping recovers plated alkali metal back into ionic form, ending when substrate depletion increases cell voltage sharply.
Interfacial Efficiency
Coulombic efficiency metrics measure the ratio of metal recovered during dissolution to the metal deposited during prior charging steps. Parasitic reactions between liquid electrolyte and metallic lithium form electrically isolated dead lithium that cannot participate in subsequent discharge cycles. Achieving reversible stripping requires high-purity solid electrolyte interphase coatings that maintain electronic insulation while permitting fast lithium ion transport.
Fluorinated electrolyte additives form stable interfacial layers that maximize metal recovery across extended cycling.
Morphological Control
Uniform current distribution across current collector surfaces prevents localized pitting and isolated island formation during discharge. High dissolution rates applied to non-uniform surfaces exacerbate metallic necking, detaching unreacted metal particles from the conductive substrate. Formulating artificial solid electrolyte interphase layers promotes reversible stripping by directing uniform ionic flux across active interfaces.
System Boundary
Temperature and discharge current density impose physical boundaries on dissolution kinetics at metal surfaces. Low operating temperatures increase charge transfer resistance, accelerating polarization and promoting structural dead metal accumulation. Operational limits derived from reversible stripping studies determine upper discharge rate limits in lithium metal battery management systems.