Nissan Tests New Metamaterial Thermal Coating

Nissan has been at the forefront of automotive innovation, recently unveiling a groundbreaking paint technology that could revolutionize the way we think about cooling systems in vehicles. Teaming up with Radi-Cool, a specialist in radiative cooling products, Nissan has developed a paint that incorporates a metamaterial, a synthetic composite material with unique properties not typically found in nature.

The metamaterial paint utilizes two microstructure particles that react to light in innovative ways. One particle reflects near-infrared rays from sunlight, which would normally generate heat within the resin of traditional paint. The second particle is the real game-changer, as it creates electromagnetic waves that counteract the sun's rays, redirecting energy away from the vehicle and into the atmosphere. Together, these particles significantly reduce heat transfer into surfaces like the roof, hood, doors, and panels.

As part of a 12-month feasibility trial conducted at Tokyo International Air Terminal at Haneda, Nissan tested the paint on a Nissan NV100 service vehicle operated by All Nippon Airways (ANA) airport services. The large, open tarmac at Haneda airport provided the perfect setting for real-world evaluation of the paint's performance in a high-temperature environment.

Results from the trial have been impressive, with vehicles treated with the metamaterial paint showing up to a 12°C reduction in exterior surface temperatures and up to 5°C cooler interiors compared to vehicles with traditional automotive paint. This cooling effect is especially beneficial when vehicles are parked in the sun for extended periods, reducing the need for air-conditioning and minimizing the strain on the battery of electric vehicles.

Dr. Susumu Miura, senior manager and expert at the Advanced Materials and Processing Laboratory at Nissan Research Center, expressed his vision for creating energy-efficient vehicles with improved cooling capabilities. He emphasized the importance of reducing the energy consumption of air-conditioning systems, particularly in the era of electric vehicles where energy efficiency is paramount.

While metamaterials have been predominantly used in the RF field, the challenges of adapting them for automotive applications were not lost on Dr. Miura and his team. They had to ensure that the paint could incorporate a clear topcoat, be applied using a spray gun, and meet Nissan's stringent quality standards. After testing over 100 samples and evaluating a thickness of 120 microns, the team confirmed the paint's resistance to various environmental factors and its repairability, paving the way for further advancements in cooling technology for vehicles.