Abstract
The present invention relates to automotive products, as well as uses thereof, which can facilitate warming of engine oil in an energy efficient and, therefore, more environmentally friendly manner. More specifically, a fluid reservoir is disclosed that includes a double walled vessel that defines a fluid containing compartment and has a self-contained region that shares a wall with the fluid containing compartment. A composition in the self-contained region at least partially covers the shared wall surface, and one or more light sources are positioned in the self-contained region to induce a phase change in the composition. The composition includes a phase-change material (PCM) and a molecular switch material. This fluid reservoir can be used to heat oil in an engine or oil pan.