Thermal and Electrical Characteristics of NCM Based Lithium-Ion Battery Separator Under Degradation

Aligned with global endeavors to address environmental challenges such as aging power infrastructures, transition from fossil fuels, and combatting greenhouse gas emissions and climate change, countries worldwide are actively pursuing energy transition policies. Consequently, energy storage technology emerges as a critical necessity, driving diverse research efforts to ensure the safety and efficacy of Energy Storage Systems components, including Power Conversion Systems (PCS), batteries, protective mechanisms, control systems, and installation protocols. This paper presents an analysis of property variations in separators, pivotal in insulating and facilitating lithium-ion reactions, employed in commercially available energy storage systems(ESS, UPS etc.) featuring NCM series batteries in Korea. Leveraging Battery Management System (BMS) data, this study forecasts battery characteristic shifts and conducts physical disassembly to validate internal alterations. Extracted samples of separator membranes from fresh cells, operational cells without anomalies, and cells exhibiting irregularities are subjected to electrochemical measurements, presenting observed changes.