How do you design battery systems to prevent and manage thermal runaway propagation?

Thermal runaway prevention involves: Cell chemistry selection (LFP inherently safer than NMC/NCA), thermal barrier materials between cells (aerogels, mica, intumescent coatings), cell spacing for thermal isolation, pack-level thermal management sized for runaway heat rejection, pressure relief vents directing gases away from occupants, battery disconnect systems, early warning detection (gas sensors, rapid temperature rise detection), and emergency cooling activation. Design targets include preventing propagation to adjacent cells for specified time (typically 5+ minutes) allowing safe evacuation. Testing per GB/T, SAE J2464, or OEM-specific protocols validates performance.