Experimental investigation of the thermal propagation, emission identification, and venting-flow characteristics of a Li(Ni0.8Co0.1Mn0.1)O2 battery module

Abstract

Aiming at improving and optimizing battery safety technology in large-format battery extensive applications, investigating thermal failure propagation, venting-flow behaviors and identifying emission components can provide significant design guidance. This work provides comprehensive experimental research on four 124Ah Li(Ni0.8Co0.1Mn0.1)O2 pouch cells connected in a configuration of one parallel and four series (1P4S). According to the experimental results, the maximum temperature of the front surfaces of cells 1–4 was 1302 °C, 976 °C, 1180 °C, and 956 °C, respectively, while the maximum temperature of the rear surfaces was 1101 °C, 938 °C, 945 °C, and 749 °C, respectively. Additionally, the failure propagation velocity for cells 1–4 was 1.15 mm/s, 0.94 mm/s, 0.88 mm/s, and 1.15 mm/s, respectively. Component identification was performed for the failed battery remains, and the solid emissions and venting gases were researched. The main component for solid particles and gases were found to be C, Ni, and H2, and their proportion was 62%, 47%, and 23%, respectively. Furthermore, the mass flow rate and critical velocity of each pouch cell were derived using the state equation for ideal gases and the isotropic flow law. The mass flow rate of cells 1–4 was 61.5 g/s, 40 g/s, 63 g/s, and 48 g/s, respectively, and the measured critical velocity was 318.5 m/s, 283.2 m/s, 267.1 m/s, and 253.5 m/s, respectively. Overall, this work provides a reference for creating safer cell-to-module designs, developing mitigation strategies, and extinguishing fire hazards for both electrical vehicles and power energy storage systems.

Keywords

• Thermal failure prorogation
• Maximum temperature
• Failure propagation rate
• Component identification
• Mass flow rate