This study offers guidance for the intrinsic safety design of lithium iron phosphate batteries, and isolating the reactions between the anode and HF, as well as between LiPF 6 and H 2 O, can effectively reduce the flammability of gases generated during thermal runaway, representing a promising direction. 1. Introduction
Lithium iron phosphate batteries, renowned for their safety, low cost, and long lifespan, are widely used in large energy storage stations. However, recent studies indicate that their thermal runaway gases can cause severe accidents. Current research hasn't fully elucidated the thermal-gas coupling mechanism during thermal runaway.
Besides, the fire effluents of LIBs can be more serious, containing lots of toxic gases such as carbon monoxide (CO) and hydrogen fluoride (HF). Larsson et al. conducted fire tests to estimate gas emissions of commercial lithium iron phosphate cells (LiFePO 4) exposed to a controlled propane fire.
A series of penetration tests using the stainless steel nail on 18,650 lithium iron phosphate (LiFePO 4) batteries under different conditions are conducted in this work. The effects of the states of charge (SOC), penetration positions, penetration depths, penetration speeds and nail diameters on thermal runaway (TR) are investigated.
Larsson et al. conducted fire tests to estimate gas emissions of commercial lithium iron phosphate cells (LiFePO 4) exposed to a controlled propane fire. All the investigations mentioned above have concentrated on small format batteries.
The nail penetration experiment has become one of the commonly used methods to study the short circuit in lithium-ion battery safety. A series of penetration tests using the stainless steel nail on 18,650 lithium iron phosphate (LiFePO 4) batteries under different conditions are conducted in this work.