The shell of the power battery pack and the protective coating of the cells in new energy vehicles extensively adopt modified silicone oil resin systems. These coatings possess three functions: insulation, waterproofing, and high-temperature resistance. They are the core coating materials for the safety protection of new energy vehicles and are different from all the coating applications in traditional fuel vehicles.
After curing, the silicone oil coating forms an insulating silicon film with a high breakdown voltage, which can prevent the risk of high-voltage leakage from the cell; the silicon molecules have balanced thermal conductivity, assisting the cell in dissipating heat and suppressing local heat accumulation, thereby reducing the risk of thermal runaway. The coating is hydrophobic and moisture-proof. When the chassis is submerged in water, it prevents water vapor from penetrating into the battery pack and avoids short-circuit faults. At the same time, the phenyl silicone oil has a maximum temperature limit of 250°C, and the short-term high-temperature of the cell will not cause the coating to melt and fail.
The safety tests of the entire vehicle show that the battery pack with sprayed silicone oil insulation coating has no leakage or short circuit phenomenon after being immersed in salt water for 48 hours; while the ordinary silicone insulation paint fails in insulation after being immersed in water for 8 hours. The water-based environmentally friendly silicone oil coating contains no heavy metals and low VOC, meeting the requirements of the green manufacturing policy for new energy vehicles.
Industry data shows that the domestic market size of silicon coatings for power batteries will exceed 4.2 billion yuan in 2026, with an average annual growth rate of over 30%. Domestic silicone oil manufacturers continue to develop high thermal conductivity and high insulation special silicone oil models. The IOTA high-temperature insulation silicone oil has been matched with many leading battery enterprises and has become a core supply category of the new energy coating raw materials.