 Projections estimate that worldwide, more than 125 million EVs will be on the road by 2030. At the heart of these advanced vehicles is the lithium-ion, leion, battery which provides the required energy storage. This paper presents and compares key components of leion batteries and describes associated battery management systems. Material and thermal characteristics are identified as critical to battery performance. This article was authored by Yu Miao, Patrick Heinen, Annette von Juwan and others.