Signal-Enhanced Dielectric Barrier Discharge Microplasma Coupled to GC for Sensitive Analysis of Low-Molecular-Weight Gases in Swollen Lithium Polymer Batteries

The real-time monitoring of low-molecular-weight gases generated during lithium polymer battery (LPB) degradation is crucial for safety. However, the simultaneous and sensitive detection of both inorganic and organic species remains a significant challenge for gas chromatography (GC). Herein, we developed an enhanced dielectric barrier discharge (DBD) microplasma detector that addresses this limitation. By leveraging the atomic or molecular emission characteristics of elements within the plasma, this detector can analyze O 2, N 2, H 2, CO 2, CO, CH 4, C 2 H 4, C 2 H 6, and polyaromatic hydrocarbons with high sensitivity. The enhanced discharge apparatus physically isolates the electrodes from the plasma chamber, thereby preventing carbon deposition and delivering superior signal strength and stability compared to conventional designs. Furthermore, the influence of discharge chamber dimensions on signal performance was systematically investigated. Under optimal conditions, the detection of limits for H 2, CO, CO 2, CH 4, C 2 H 4, and C 2 H 6 were 6, 0.3, 0.3, 0.5, 0.1, and 0.1 μmol/mol, respectively, significantly outperforming previous reports and commercial detectors. The accuracy of this strategy was confirmed with standard gases, and its practical utility was successfully demonstrated by analyzing gases from real swollen LPBs. This work provides a highly promising and universal solution for sophisticated gas analysis in LPB safety assessment.