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Degradation mechanisms and early detection of moisture-contaminated lithium-ion batteries

By Shunling Li, Zhigang Ai, Xiaoman Li
2026
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This study presents a systematic investigation of moisture-contaminated lithium-ion batteries through controlled perforations, combining performance analysis with an innovative early detection method. Performance testing revealed severe capacity degradation (<80% retention) and significant swelling (30-65%) in damaged batteries under both room-temperature cycling conditions and high-temperature/high-humidity storage (85°C/85% RH). Microscopic analysis uncovered the underlying mechanisms: moisture-induced Solid Electrolyte Interphase/Cathode Electrolyte Interphase (SEI/CEI) layer destruction and electrolyte decomposition, evidenced by structural deterioration and transition metal dissolution. Notably, our newly developed algorithm successfully identified compromised batteries at an early stage (>96% capacity retention) by analyzing capacity fade patterns, enabling preemptive intervention. Furthermore, Accelerating Rate Calorimetry (ARC) testing yielded unexpected results, with perforated batteries showing higher thermal runaway initiation temperatures (200±9°C vs 186±1.3°C) despite their compromised electrochemical performance. These findings advance both fundamental understanding of battery degradation and practical safety management strategies.
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