Study of the fire hazards of lithium-ion batteries at different pressures

The fire behavior of lithium-ion battery is affected by the environment conditions. In this paper, an experimental study is performed to assess the fire hazards of lithium-ion batteries at different atmospheric pressures by means of the in-situ calorimeters built in a sea-level city Hefei (100.8 kPa, 24 m) and a high altitude city Lhasa (64.3 kPa, 3650 m), respectively. The fire hazards of lithium-ion batteries were characterized by measuring the ignition time, mass loss, heat release rate (HRR), and total heat release (THR). From the results, the ignition time of single battery decreases with the ascending of the state of charge (SOC), whiles the mass loss, and ejection energy increase with that at two pressures. The increment of altitude causes the battery to ignite faster, while the mass loss, heat release rate and total heat release both for single battery and bundle batteries decrease at low pressure. The total heat release in the bundle increases with the battery numbers in a power function. The coefficient of the proportionality is pressure dependent.