As power device integration continues to increase, the heat flux density inside electronic control systems has risen significantly. Against this backdrop, the role of potting compounds is shifting from simple "physical filling" to a combined function of "thermal conductivity plus electrical insulation," making them an indispensable part of new energy electronic control system design.

The core performance of thermally conductive potting compounds lies in two dimensions. The first is thermal conductivity, typically measured by thermal conductivity coefficient, with common products covering a range of 1.0 to 3.5 W/m·K, selectable according to heat source power and heat dissipation conditions. The second is electrical insulation. High-quality potting compounds generally have a dielectric strength of no less than 20 kV/mm, maintaining a reliable insulation barrier under high-voltage environments. Additionally, UL94 flame retardancy ratings and long-term temperature resistance grades are important reference indicators during material selection, as they relate to product safety under abnormal operating conditions.

In the new energy vehicle sector, the application scenarios for thermally conductive potting compounds are well-defined. The battery management system (BMS) modules of traction batteries require multi-channel temperature acquisition and balancing control within a compact space; potting compounds secure components while helping conduct heat to the metal housing. Onboard inverters and charging pile power boards face higher switching frequencies and power losses, imposing stricter requirements on the thermal conductivity efficiency and thermal cycling stability of potting compounds. Low-viscosity potting compounds offer clear advantages in such complex cavities, allowing full filling of gaps under vacuum assistance and reducing localized overheating caused by voids.

From a process reliability perspective, the curing shrinkage of potting compounds directly affects the mechanical stress on encapsulated components. Materials with excessive shrinkage may pull on chips or solder joints during curing, creating failure risks under long-term operation. Therefore, low-shrinkage formulations are preferred in precision electronic packaging. At the same time, the coefficient of linear thermal expansion of the potting compound should be as close as possible to that of the PCB substrate and metal heat sink to reduce interfacial stress during temperature cycling. The hardness after curing is also worth attention. While excessively hard products offer high mechanical strength, they increase the difficulty of later repair and component replacement.

In summary, reliable potting is an important measure to ensure the stable operation of electronic control systems in complex environments such as high humidity, vibration, and dust. By reasonably matching performance parameters such as thermal conductivity, insulation, and flame retardancy, potting compounds provide sustained protective value throughout the long-term service of new energy equipment.

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