In Situ Lithium Plating Monitor for Lithium-Ion Batteries Enabled by Operando Pressure Detection

Abstract

Lithium plating on graphite anode surface in lithium-ion batteries accelerates the capacity degradation of batteries, reduces their lifespan, and poses potential danger such as short-circuiting. Hence, real-time, non-destructive, in-situ monitoring of lithium plating behavior and dynamic regulating the charging strategy accordingly is crucial for the healthy operation of fast-charging lithium-ion batteries during low temperature and high C-rate charging. Our research establishes that the plateau in the pressure differential curve (dP/dQ) serves as a definitive indicator of lithium plating occurrence lithium plating growth. The dP/dQ plateau exhibits strong reliability, accuracy, sensitivity, applicability, and practicality in identifying lithium plating growth which has a significant damage on battery capacity Furthermore, we demonstrate that during low-temperature and high C-rate charging, identifying the lithium plating boundary using the dP/dQ plateau and dynamically regulating the charging cut-off voltage within lithium plating boundary can maximize the operational voltage range, thereby enhancing energy output (increasing energy output by 15.2% with only a 0.8% increase in capacity loss over 30 cycles). This methodology promises a practical strategy for extending the operational health and efficiency of fast charging lithium-ion batteries.

Keywords: Li-ion batteries, Lithium plating, Operando pressure, dP/dQ