Electric vehicles with lithium-ion batteries can be especially dangerous when they catch fire. The good news is electric vehicle (EV) battery fires don’t happen often, however when an EV does catch fire, the consequences can be problematic. EV fires can continue to reignite for days after initially being extinguished. The batteries can enter thermal runaway thanks to several causes: improper thermal management, manufacturing defects, overcharging or vehicle crashes.
The thermal management system and materials are key to keeping the batteries in the optimal temperature range. A key challenge is the constantly evolving design of batteries at both a cell and pack level. Battery chemistry is evolving with higher nickel cathodes being adopted, LFP (lithium iron phosphate) batteries making a resurgence and more attention being paid to solid-state batteries. LFP batteries are said to be safer and solid-state have often been touted as completely safe. Other major automakers including Ford, and VW are also substituting LFPs for nickel or cobalt formulations.
Comparison between LiFePO4 and Li-ion Batteries (Texas Instruments, 2016)
Outside the cell, transitioning towards cell-to-pack designs, stacking all the cells together into a battery pack without the separate module housings makes management of thermal runaway propagation more difficult. This presents several material level opportunities around the cells within a battery pack. These include thermal interface materials (TIMs), thermal insulation, dielectric materials or coatings, fire-retardant materials, and many more.
At Sotera, we always consider the hazards associated with electric vehicle fires while proposing fire safety measures for carpark. Reach out to our team if you’d like to discuss any of the solutions to mitigate any fire hazards related to electric vehicle fires in your building.
At Sotera we are committed to incorporating practical and cost-effective fire safety solutions in the early stages of project design. We would love the opportunity to assist with your project, so get in touch with us at either of our offices in Brisbane or Gold Coast.