Meaning
Pre-formed thermal interface sheet made of silicone elastomer filled with thermally conductive ceramic particles. A silicone gap pad is placed between battery cells and the cooling plate to fill microscopic air gaps and facilitate heat flow. The pad provides electrical insulation while maintaining a low thermal resistance.
Compression Behavior
Conformability of the pad depends on its hardness, measured on the Shore OO scale, and the applied assembly pressure. Under mechanical preload, the elastomer deforms to match the irregular surfaces of the pouch or prismatic cell casings. This deformation minimizes contact resistance and maximizes the heat transfer area.
Sourcing Metric
Sourcing teams evaluate different pad formulations based on their thermal conductivity, dielectric breakdown voltage, and compression-set properties. Procurement contracts specify these metrics to ensure that the pads can withstand decades of thermal cycling without cracking or losing contact. Material outgassing is also monitored to prevent contamination of electronic components.
This evaluation ensures that the thermal solution remains stable over the vehicle entire warranty period.
Manufacturing Assembly
Automated pick-and-place equipment applies pre-cut pads to the cold plate to ensure high placement accuracy. Consistent thickness and positioning are required to prevent localized high-pressure points that could damage the delicate cell casings during compression. These assembly steps are monitored using computer vision systems.
Real-time feedback helps to maintain high quality across production runs.
