NMC materials, with high Ni content, represent promising cathode materials for Li-ion batteries which demonstrate higher specific capacities in comparison to traditional cathode materials. The challenge of using such materials is related to the structural changes and the associated specific capacity fading during the electrochemical cycling of batteries. With this master’s thesis, we have shown the positive influence of the polymer coating on the stability of the material structure and the electrochemical performance of such batteries. Two different types of polymers have been used for coatings on the secondary particles of NMC, an electron conductive polymer PEDOT:PSS and an ion conductive polymer PAA. The results of electrochemical cycling and scanning electron microscopy (SEM) show that the optimal percentage of added polymers is 3 wt. %. We show that by increasing the ion-conducting component, we achieve higher initial specific capacities as well as better cycling stability. The determined optional ratio between PEDOT:PSS and PAA are between 25/75 and 15/85. Using thermogravimetric analysis and infrared spectroscopy we confirmed that the synthesized coatings contain both polymers PEDOT:PSS and PAA and coating percentages are equal to percentages of added polymers.
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