The problem of high fossil fuel and electricity consumption for operation of air conditioners and space heating can be solved by replacing them with the energy storage materials. Certain materials can absorb and release thermal energy when it is necessary. The most favourable are the materials, which can store the latent heat, as the heat required to change the temperature is stored, as well as the heat required to change the physical state of the phase change materials (PCM). The melting temperature of PCM determines the field of application of composite material, which means, that the PCMs which have melting temperature in the room temperature range (25℃), are the most suitable for use in the residential buildings. Most often these are paraffin waxes and fatty acids. These compounds must be properly incorporated into the carrier material/matrix in order to maximize efficiency and to prevent fire, as the organic compounds are flammable. A suitable method of incorporating is shape stabilization of PCM in the matrix at elevated temperature, then cool below the glass transition temperature. Composite materials for latent heat storage have low thermal conductivity. Therefore, carbon-based materials (dopants) are added. In addition to improve thermal conductivity, dopants also provide better stability of PCM in the matrix. In this thesis are described both examples of the use of carbon-based dopants in composite materials for latent heat storage. Morphology, thermal and mechanical properties and thermal conductivity of these materials are mainly discussed. According to the results obtained from the literature, composite materials for latent energy storage are stabile after a number of heating and cooling cycles. Melting point and glass transition temperature of the matrix are maintained and are independent of the concentration of dopants. The matrix is stable at the melting temperature of the PCM, which means, that it can retain the PCM, when it is in a liquid state and prevent leakage. The amount of stored latent energy is high enough for practical use and is between 100 J/g and 200 J/g, depending on the proportion of each component. In the case of mixture of 0,8 wt.% graphene oxide with 19,2 wt.% matrix (mixture of wood powder and polyurethane) and 1,2 wt.% graphene oxide with 18,8 wt.% matrix, the thermal conductivity increased eightfold compared to pure PCM and pure matrix.
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