Adaptive charging strategy with temperature rise mitigation and cycle life extension for li-ion batteries

Charging battery with a large C-rate current to shorten the charging time (CT) will induce the drastic electrochemical reaction, and thus bring about the significant temperature rise (TR), energy loss, performance degradation, and safety concern as well. To tackle this problem, an adaptive charging strategy with TR mitigation and cycle life extension is proposed in this study. Based on the relationship between the charging current and remaining state of charge (RSOC) which is extracted experimentally, a baseline charging current is determined first. To control the temperature rise further, a fuzzy TR controller (FTC) is devised to fine-tune the charging current according to the temperature gradient. Thus an adaptive charging current with temperature rise suppression mechanism can be generated dynamically in the entire charging process. The proposed charging strategy is validated by means of experimental studies and compared with the conventional constant current-constant voltage (CC-CV) method. The results show that the average temperature rise, charging efficiency, and estimated cycle life have 31.24%, 2.06%, and 57.3% of improvement respectively as compared with that of the conventional CCCV obtained.