Experiment investigation for interconnected effects of driving cycle and ambient temperature on bidirectional energy flows in an electric sport utility vehicle

Abstract

The constrained driving range has emerged as a pivotal quandary impeding the advancement of electric sport utility vehicles (ESUVs). In this study, energy flow tests were executed on an ESUV to investigate interconnected effects of driving cycle and ambient temperature on bidirectional energy flows throughout the entire driving range. The results reveal that air conditioner singularly imposes a substantial surge in energy consumption at high-temperature settings. Notably, energy utilization efficiency (ηuti) reaches its zenith under Fixed speed cycle at room temperature (FSR_R) and energy recovery efficiency (ηrec) attains its peak under World Light Vehicle Test Cycle at room temperature (WLTC_R). Nevertheless, ηuti and ηrec attain their acme at room temperature and reach their nadir under low-temperature conditions, regardless of the specific driving cycle employed. Battery average temperature exhibits an ascending trajectory at room temperature and displays cyclic fluctuations at high temperature, while first increasing rapidly and then decreasing gradually in low-temperature ambient. Battery output energy per cycle initially decreases and eventually stabilizes with increasing the cycle count, and the battery recovery energy shows an initial upward trend followed by a stabilization phase. These findings provide empirical substantiation and prescriptive insights for mitigating energy consumption and enhancing driving range of ESUVs.