Gelled graphite/gelatin composites for latent heat cold storage

authors	Vitorino, N; Abrantes, JCC; Frade, JR
nationality	International
journal	APPLIED ENERGY
author keywords	Shape stabilized composites; Phase change materials; Cold storage; Thermal properties; Fusion kinetics
keywords	THERMAL-ENERGY STORAGE; PHASE-CHANGE MATERIALS; COLLAGEN
abstract	Aqueous suspensions of graphite were shape stabilized by the additions of collagen and characterized as phase change materials for cold storage with enhanced thermal conductivity. Collagen addition stabilized the graphite suspensions in aqueous media without requirements for additional stabilizers or previous functionalization. Gelation at room temperatures prevented sedimentation of graphite particles. SEM of dried samples confirmed nearly random distribution of graphite particles. These gelled suspensions with enhanced thermal conductivity were tested for latent heat cold storage. The thermal response was retained upon repeated phase change cycles, and impedance spectroscopy was used to monitor these cycles. The response time upon phase change was somewhat longer than predicted by taking into account the values of thermal diffusivity and the estimated value of Stefan number, probably due to significant interfacial resistance to heat transfer, combined with discontinuities caused by volume expansion upon phase change. (C) 2012 Elsevier Ltd. All rights reserved.
publisher	ELSEVIER SCI LTD
issn	0306-2619
year published	2013
volume	104
beginning page	890
ending page	897
digital object identifier (doi)	10.1016/j.apenergy.2012.12.014
web of science category	Energy & Fuels; Engineering, Chemical
subject category	Energy & Fuels; Engineering
unique article identifier	WOS:000316152700086