In-situ explosion limit analysis and hazards research of vent gas from lithium-ion battery thermal runaway

Abstract

The explosion of thermal runaway gas of lithium-ion batteries may trigger a thermal runaway domino effect in multiple batteries. Therefore, the research on the explosion limit and explosion power of them is important to assess the danger of lithium-ion batteries. In this work, an innovative combination of gas composition analysis and in-situ detection was used to determine the BVG (battery vent gas) explosion limit of NCM 811 (LiNi0.8Co0.1Mn0.1O2) lithium-ion batteries, which revealed that as the battery SOC (state of charge) increases, LEL (lower explosion limit) first increases and then decreases, UEL (upper explosion limit) continues to increase. It was also verified that the BVG explosion range increases as the battery SOC increases, revealed the opposite trend of the lower explosion limit with the multi‑carbon chain gas fraction, and in addition, the quantification of the explosion consequences provided recommendations on the SOC values for safe storage.