Numerical study of mini-channel liquid cooling for suppressing thermal runaway propagation in a lithium-ion battery pack

Suppressing thermal runaway propagation (TRP) in lithium-ion battery (LIB) packs by cold plates gained great popularity recently due to the related urgent safety concerns. TRP in a LIB pack and the suppression method using liquid cooling cold plates are numerically investigated in this study. Varying mini-channels widths (W) and coolant flow velocities (u) in cold plates were employed to examine their effects. The numerical model was first verified by previous experimental measurements, and then several sets of TRP scenarios were simulated. The results showed that without cold plates all batteries suffered thermal runaway (TR), and both the heat release rate and total released heat during TR were very high. When using cold plates with fixed W of 5 mm, u = 0.1 m/s delayed occurrence of TRP but failed to eliminate TRP. u = 0.2 m/s partially inhibited TRP, and u ≥ 0.3 m/s completely suppressed TRP. For fixed u = 0.2 m/s, TRP, partial TRP, and non-TRP occurred in W ranges of 3–4 mm, 5–6 mm, and ≥ 7 mm, respectively. Meanwhile, the heat loss to coolant and its ratio to total released heat were quantitatively examined. A critical curve separating the TRP and non-TRP regimes was identified to characterize the critical condition for suppressing TRP.