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This paper studies how the user charging practice affects battery degradation over time. To achieve this objective, a system oriented simplified aging model based on the literature is proposed. The differential calculation of the capacity loss is used for infinitesimal variations. The model inputs are the battery state of charge, the battery temperature and the cumulative number of full equivalent cycles. The output is the battery state of health. This model is identified and validated with experimental aging tests from the Renault Zoe 41kWh battery manufacturer. The battery model (electro-thermal and aging) interconnects with the vehicle traction model complete the system model. The battery electro-thermal and traction models are also validated with measurements on the studied vehicle. The Energetic Macroscopic Representation (EMR) formalism organizes in a unified way the interconnections of all the sub-system models. The impact of the charging interval and SoC on the battery aging is then studied. Five charging scenarios are studied by simulation while keeping the driving phases and the charging current the same. In these conditions, the average SoC is the main contributor for the battery aging. Compared to daily charge of the EV, a charge every 4 days extends the time to reach 80% of state of health by 36 % due to lower average SoC. The daily driving distance is fixed for every studied scenario.

This paper shows that the way of charging electric vehicle influences the battery aging. A simplified lithium-ion battery calendar aging model is used. This simple battery lifetime model, estimates the capacity fade including the effects due to the temperature and the state of charge. The reference vehicle is a 2018 Nissan Leaf. The entire vehicle, including the battery, the traction system and the road, is simulated with a reference velocity cycle. The energetic macroscopic representation of the vehicle is used for model and control organization. Two charging scenarios are defined. The first scenario corresponds to a daily vehicle charge, while the second one corresponds to one charge every 5 days. The model including the aging of the battery shows a significant difference between the two scenarios in term of capacity degradation through years.