Since they were first introduced in the early 1990's, lithium ion batteries have enjoyed unprecedented growth and success in the consumer marketplace. Combining excellent performance with affordability, they have become the product of choice for portable computers and cellular phones. Building on the same energy and life cycle attributes, which marked their consumer market success, but adding new high power storage capability, lithium ion technology is now poised to play a similar role in the transportation sector. With major programs in various aspects of electric and hybrid electric vehicles, Saft has developed a family of battery products which address the power and energy storage where light weight, long life, and excellent energy or power storage capabilities are needed. Significant progress in the packaging and control of high power, yet compact, batteries has been accomplished for a variety of vehicle applications. This paper discusses the thermal management, packaging strategies, and electronic monitor, protection, and control of this family of products and their potential applications. In the first section, it describes the effort related to high energy (HE) LiON® typically for electric vehicle (EV) use, and in the second section it describes the effort related to high power (HP) LiON® typically for hybrid electric vehicle (HEV) use.