U.S. patent application 20150240759 (applicant GM Global Technology Operations, Troy, Mich.):
"A number of variations may include a product including a housing including at least one phase change material and a medium constructed and arranged for thermal energy transfer to or from a vehicle fuel. ... [E]thanol fuel may be prone to clogging of the vehicle engine within the surroundings during undesirable conditions. This clogging may cause the vehicle engine to stall or not start upon desired ignition. ... [W]hen the conditions become undesirable ... the phase change material within the housing may at least partially freeze or solidify, releasing thermal energy through the medium and into the ethanol fuel. The increased thermal energy to the ethanol fuel may allow at least a portion of the ethanol fuel's gel, wax-like, or crystalline state to liquefy or melt enough to start or continue to run the vehicle engine."