Core electrification technologies require developments in battery packs, chargers, electric motors, and thermal management strategies to improve their performance, longevity, reliability and safety. The next battery technology leap relies on novel thermal management strategies and packaging architectures, realized as intelligent battery thermal management systems (BTMS), which can optimally control the thermo-electrochemical phenomena occurring inside the batteries to maximize performance, minimize degradation, enable fast-charging protocols, and accelerate a seamless transition of degraded electric vehicle (EV) batteries into less-demanding second-life stationary systems. This Lecture will present current engineering challenges and opportunities on EV thermal management, with a focus on our research on multiscale hierarchical design, modelling, and optimization approaches to overcome cooling and heating challenges across multiple physical domains and length scales, from battery electrodes, to battery cells, battery packs, to EV thermal management systems.