Study on Gas Production Characteristics of Lithium Iron Phosphate Battery Module under High and Low Temperature CO2

The explosion catastrophes resulting from the lithium-ion battery thermal runaway gas production has severely suppressed the application and development of lithium-ion batteries energy storage systems in recent years. CO
2
has good insulation performance and deactivation performance and is suitable for gas explosion proof of electrical equipment The 2.56 kWh lithium iron phosphate battery module's (LIBM) thermal runaway gas generation characteristics are suppressed using low temperature carbon dioxide (L-T CO
2
) and high temperature carbon dioxide (H-T CO
2
) by different injection modes in this work. With H-T CO
2
whole cabin jet, explosive gas concentration in LIBM decreases at a faster pace than with L-T CO
2
whole cabin jet, and the CH
4
concentration drops to below the explosion limit in just 6 min. When L-T CO
2
is injected into the module, the LIBM explosive gas concentration declined more quickly than the H-T CO
2
, and the CH
4
concentration reached below the explosion limit in under 21min. The factors influencing the explosive gas drop rate are examined. H-T CO
2
sublimates quickly onto dry ice under the whole cabin jet, and explosive gas may be diluted effectively, the influence of diluted gas is stronger than that of cooling inhibition. In the injection module, the cooling performance of L-T CO
2
is better, and the gas production rate of lithium iron phosphate is slower. Compared to diluting gas, low temperature inhibition has a stronger affect. The findings indicate that lowering chemical processes within the battery and diluting the explosive gas concentration can both greatly speed up the explosive gas concentration decline. This information can be used to guide LIBM energy storage systems in preventing gas explosions.