Coupon-Level Experimental Material Screening of Carbon Fiber-Reinforced Polymers under Thermal Runaway Conditions for eVehicle Applications

Abstract:

The shift towards electric mobility needs extensive research into battery modules, particularly in relation to safety due to the high energy density of Li-ion batteries. Battery casings must be able to protect the module from external impacts while also containing any potential danger in the event of internal failure. This study presents a comprehensive qualitative screening of thermoset and thermoplastic carbon fiber-reinforced polymers (FRP) used in automotive and aerospace applications under thermal runaway (TR) conditions, to identify suitable materials for battery enclosures. The test setup is an adaptation of the UL 2596 standard with a hexagonal array of seven 21700-format cells. The results indicate that CF-PEEK, CF-PPS, and an aerospace-grade epoxy, CF-EP_str (primary structural material) effectively contain the TR with low damage using the current setup. Medium damage was observed in CF-PC, CF-bio-based phenolic, while non-structural CF-epoxy and CF-PA6 failed to contain the TR. This qualitative study serves as an initial screening process to narrow down materials for further in-depth analysis, emphasizing the need for reproducible TR events for accurate assessment.

• Periodical: Materials Science Forum (Volume 1152)
• Pages: 3-10
• DOI: https://doi.org/10.4028/p-o0UK9x
• Online since: June 2025
• Authors: Margarita Etchegaray Bello*, Özge Özsoy, Jan Schöberl, The Anh Dieter Nguyen, Leo Heidemann, Evan O'Connor, Moritz Schuhmann, Klaus Drechsler
• Keywords: CFRP, Evehicles, Thermal Runaway, Thermoplastic, Thermoset

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