Life Prediction Modeling of Lithium-Ion Batteries based on Electrochemical Analysis

The lithium-ion battery has been considered a good candidate for use in electric vehicle energy storage devices owing to its stability, high–power density, and high cycle–life. However, there are few studies about the quantitative reliability of lithium-ion battery. Therefore, in this study, a quantitative reliability analysis for lithium-ion battery is carried out. The study consists of three parts. First, mathematical model is established based on electrochemical theorem. Secondly, the capacity fading is examined by focusing on the growth of solid electrolyte at the Negative electrode, which is considered the canonical degradation mechanism of the battery. It is shown that a simple single-particle model is enough to explain experimentally observed capacity fading of a battery with negative electrode. The third part of this study focuses on the reliability estimation of lithium-ion battery. The un-reliability or failure condition is defined as when a battery’s capacity after recharging drops to 80% of its nominal capacity. When considering the usage situation, the distribution of driving distance per day of a vehicle is transformed into the depth of discharge and also randomized. The mean and standard deviation of life and quantitative reliability of the battery are estimated accordingly. Three different environmental and usage situations are considered in particular.