Resumen:
This article proposes a Similarity-Based-Modeling (SBM) approach capable of characterizing the degradation process of a lithium-ion (Li-ion) battery when discharged under different current rates and different State-of-Charge (SOC) ranges. The degradation process can be represented through a biexponential model. Understanding the degradation process is a matter of utmost importance since the after each time the battery is used, the availability to store and deliver energy decreases. Even though manufacturers provide important information that explains the degradation process of the Li-ion batteries when used always under the same conditions, this information many times is not enough due to the different ways a single battery can be used through its lifespan. This behavior creates the necessity to use the available information and extrapolation techniques to model the degradation process when variable operating conditions are present in each cycle. This will allow the user to understand when the Li-ion battery will complete its lifespan with a known uncertainty, aiding a possible decision-making task. In this regard, it is possible to determine the equivalent cycle-by-cycle efficiency which has low values at the beginning of the degradation process until it reaches a higher and steady value. The lifespan of the batteries is analyzed through the use of Monte Carlo simulations which intends to represent a more realistic way of how the batteries are used.
