In recent years, concern about climate change has been increasing due to its increasingly evident effects and electrification is the most relevant alternative to the traditional combustion engine. The battery pack is the heart of the system and Li-ion cells are the most used. Weight and thermal management are the main factors affecting EV performance and efficiency. A scaled-down version of an innovative battery pack designed for high-voltage applications on BEVs, which adopts an immersion cooling system while implementing cell-to-pack integration, is the subject of this thesis. The work carried out is divided into two parallel activities. On one hand, the development of the electrical model of the 48V battery pack with a capacity of 20 Ah.