Faster and Healthier Charging of Lithium-Ion Batteries via Constrained Feedback Control

Abstract

A constrained feedback control strategy designed on the basis of a simplified electrochemical–thermal model is considered for the fast and healthy charging of a lithium-ion battery cell. The constraints ensure avoidance of side reactions and operating modes that yield premature aging (healthier charging). They are enforced through a reference governor approach, hence requiring a low computational burden. A systematic approach is presented for model identification and control law design. The method is first validated on a detailed battery simulator based on the Doyle–Fuller–Newman model combined with a thermal model. Next, it is validated experimentally through battery-in-the-loop long-term aging campaigns, and the results show that the charging time is reduced by 22% while simultaneously ensuring a longer lifetime (26% less capacity degradation) compared to a 2C constant-current/constant-voltage (CCCV) approach. Compared to recommended C/2 CCCV, our method charges the battery 70% faster and degrades it similarly despite more demanding operating conditions.