In the thermal management system of new energy vehicle batteries, phenyl silicone oil itself is not a typical phase change material, but its thermophysical properties are related to the application of phase change materials in the thermal management system, and phenyl silicone oil can indirectly optimize the thermal management effect through its own performance. The following is an analysis from three dimensions: the characteristics of phenyl silicone oil, the application of phase change materials in the thermal management system, and the potential role of phenyl silicone oil in thermal management:

Basic characteristics of phenyl silicone oil
Wide temperature resistance range: phenyl silicone oil has excellent thermal stability and can maintain stable physical and chemical properties in high temperature environments. Its flash point is greater than 300°C, and the gelation time in hot air at 250°C is as long as 1750 hours, showing excellent heat resistance.
High viscosity-temperature coefficient: Compared with dimethyl silicone oil of the same viscosity, phenyl silicone oil has a higher viscosity-temperature coefficient, which means that its viscosity is less sensitive to temperature changes, which is conducive to maintaining stable lubrication and sealing performance in environments with large temperature changes.
Strong radiation resistance: Phenyl silicone oil has good radiation resistance and can operate stably for a long time under radiation environment, which is an important advantage for the thermal management system of new energy vehicle batteries.
Application of phase change materials in thermal management systems of new energy vehicle batteries
In the thermal management system of new energy vehicle batteries, phase change materials (PCM) are widely used for heat dissipation and temperature control of batteries. PCM can absorb or release a large amount of heat during the phase change process, thereby maintaining the stability of the battery temperature. Common PCMs include paraffin, fatty acids, etc., which have suitable phase change temperatures and high latent heat values.

Potential role of phenyl silicone oil in thermal management systems
As a heat exchange medium: Although phenyl silicone oil itself is not a phase change material, its excellent thermal stability and lubricity enable it to be used as a heat exchange medium to transfer heat in the battery thermal management system. By combining with PCM, phenyl silicone oil can further improve the efficiency of the thermal management system.
Optimizing PCM performance: Phenyl silicone oil can be mixed with PCM to improve the thermal conductivity and stability of PCM. For example, adding phenyl silicone oil as an additive to PCM can increase the thermal conductivity of PCM, thereby accelerating the transfer of heat.
Extend PCM service life: The antioxidant and radiation resistance of phenyl silicone oil helps protect PCM from oxidation and radiation damage, thereby extending the service life of PCM. This is of great significance for the battery thermal management system of new energy vehicles that require long-term stable operation.