The lecture will provide an overview of lessons learned when designing battery thermal management systems for advanced vehicles. We will start by understanding where the heat is generated in a cell, the efficiencies of power and energy cells, and what type of battery thermal management solutions are available in today's market. We will then investigate three different battery pack thermal management strategies employed by the OEMs – water cooling, air cooling and active (vapor compression) cooling- and outline the advantages and disadvantages of each technology. We will also delve into the Department of Energy's extreme fast charging program describing how the cell and module thermal design needs to be improved to meet the lifetime and safety expectations of the consumer. Finally, we will introduce the ultimate thermal challenge – cells entering into thermal runaway and what strategies are being employed to control or mitigate this phenomena. In the end, we hope to show that energy storage systems are varied, and each application requires a unique thermal solution to address today's technological barriers.
Matthew Keyser joined NREL in 1992 and today manages the vehicle electrification group in the Transportation and Hydrogen Systems Center. This group includes the electrochemical energy storage team, which conducts modeling, simulation, and systems evaluation activities to assess and optimize energy storage components at the materials, cell, pack, and systems levels, as well as the power electronics team, which develops power electronics and electric motor technologies with greater dependability, efficiency, and durability. During his decades-long tenure at the lab, his research has focused on various aspects of advanced vehicle technologies and systems. He developed an assortment of finite element thermal and structural models for hybrid electric vehicle components. He also fostered the growth of NREL's energy storage research equipment and facilities, which now span more than 9,000 square feet of laboratory space and enable electrochemical material fabrication, safety analysis and characterization, and world-class thermal characterization. During his time at NREL, he has licensed three patents and has been awarded four R&D 100 Awards, one Governor's Award for High Impact Research, and was recognized in 2002 by the Massachusetts Institute of Technology's Technology Review magazine as one of the Top100 innovators in the world under the age of 35. Before coming to NREL, he worked in the military industry, performing structural and thermal finite element analyses for power supplies subjected to severe vibration, shock, and thermal environments.