Encapsulated paraffin-type phase change materials are considered important candidates for thermal energy storage applications. In this paper, we present icosane coated in a layer-by-layer fashion using the weak poly electrolytes poly(acrylic acid) and poly(allylamine) in order to create ultra-thin cross-linkable and robust polymer encapsulations with storage capacities close to the pristine icosane. After coating, SEM images displayed an average particle size between 20 and 50 Generally, smooth surface structures of the coated particles compared to uncoated icosane-surfactant particles, H-1 NMR and FT-IR spectra as well as fluorescence imaging confirmed the successful encapsulation. Calculations of the PCM content revealed that the final product consisted of 88.6% core material. Accordingly, the resulting PCM capsules showed high storage capacities of 199.1 J g(-1) close to the original value of pristine icosane (223.6 J g(-1)). Thermal stability was confirmed by TGA, revealing an increased resistance to thermal degradation of the coated particles (T-10,T- bulk = 175.7 degrees C and T-10,T-capsule = 186.8 degrees C). Moreover, repeatability and reliability of the phase change behavior were confirmed in thermal cycling experiments including 100 heating-cooling cycles with no observable influence on the performance of our material.