Lithium-ion batteries (LIBs) are earning an increasing attention for the decarbonisation of the industry as in the energy and the automotive sectors. As energy storages they are applied as energy and power source; therefore, the prediction of the battery life is fundamental. In this way the understanding of the batteries aging and the monitoring of the degradation on-board are good strategies. In this thesis work this purpose was pursued by studying the aging mechanisms and their consequences from a more global perspective. That was done by understanding and quantifying dominant cell degradation modes (DMs) such as Loss of Lithium Inventory (LLI) and the Loss of Active Material on both electrodes (LAMn & LAMp).