Advances in Tank Heaters Based on PTC (Positive Temperature Coefficient) Plastic Nanomaterials

The global trend on emission reduction is leading to a wider diffusion of SCR systems for diesel engines and to the introduction of WI (water injection) systems in gasoline engines. Cars are equipped with tanks for water and urea solutions (AD-blue). Both liquids can freeze in the car operative temperature range: the tanks must be equipped with heaters to guarantee a sufficient amount of additives in liquid form in any condition. We propose solutions based on plastic PTC (in the following nanoPTC) effect nanomaterials for thermal management of those liquids. The proposed heaters can be molded in any shape, following the specific constraints of each tank, in carpet like shapes for a distributed heating of the tank, or in bulky components integrating sensors housings, pipes, pumping systems or in the packaging of other components. The PTC effect is distributed avoiding overheating in parts with poor thermal exchange (dry condition). The advantages on existing technologies can be summarized as follows: higher efficiency, safer operation, no additive damage (urea is decomposed if overheated), arbitrary shape design, low cost. The evolution of the technology, presented for the first time in 2017 [1], will be shown and the obtained performances compared with currently used technologies.