Degradation behavior of lithium-ion batteries in consumer electronics is strongly influenced by real-world operating conditions, yet evaluations based on batteries recovered from consumer-used devices remain limited. In this study, commercial pouch-type lithium-ion batteries extracted from used iPad Air 4 and iPhone 13 Pro devices were systematically  evaluated under controlled state-of-charge (SOC) windows, temperature conditions, and high-temperature storage. Narrow SOC operation suppressed voltage hysteresis growth and preserved discharge plateaus compared to full-depth cycling. Temperature-dependent tests revealed increased polarization and capacity limitation at low temperature, while elevated temperature accelerated voltage distortion and capacity decay. High-temperature storage further induced irreversible voltage shifts and reductions in voltage and energy efficiency. These results demonstrate that voltage-based indicators provide a practical and effective approach for diagnosing operating-condition-dependent degradation in commercial batteries 

recovered from real consumer devices, offering realistic insights for battery safety evaluation, quality management, and standardized degradation assessment.