Lexicographic model predictive control strategy in ageing-aware optimal charging procedure for lithium-ion batteries

Abstract

A proper battery management system has to find the optimal trade-off between fast charging and ageing effects minimization while satisfying safety constraints. Such a task can be formulated as a constrained multi-objective optimization problem with competitive goals, where a mathematical model is exploited in the description of the battery behaviour. In this paper, for the first time in the lithium-ion batteries context, a priority-based model predictive control that relies on a modified lexicographic approach is proposed, which is suitable for strictly convex objective functions. In particular, the considered objectives in order of priority are fast charging and ageing reduction. Moreover, a shrinking-horizon termination strategy is presented, thus enhancing a finite-time reaching phase of the state of charge reference. The effectiveness of the presented algorithm, coupled with a state observer, is tested on a numerical implementation of the well-known Pseudo-Two-Dimensional model and the results are compared with a conventional model predictive control procedure.