Development of off-road hybrid-electric powertrains and review of emerging battery chemistries

This paper will inform the reader on two areas of research and development that QinetiQ is active in: (1) Off-road hybrid-electric vehicle powertrains The first section will describe the technical challenges associated with designing powertrains for off-road vehicles with military levels of performance - involving extremely high levels of torque and, in the case of tracked vehicles, exceptionally high power requirements for skid steer manoeuvres. It will reflect on techniques applied by QinetiQ over the past 17 years of research and development, with an emphasis on the balance between mechanical and electrical equipment to achieve overall system benefits in mass, volume and efficiency. Examples of past and current developments will be presented in this context, including the 6×6 hybridelectric demonstrator vehicle and the E-X-Drive® electromechanical transmission for tracked vehicles. (2) Emerging battery chemistries The second section will provide an objective review of emerging advanced battery chemistries and their respective advantages & disadvantages for use in vehicles. This review will draw upon both literature and QinetiQ´s experience in developing and small-scale production of prismatic soft-pack cells with advanced electrode materials and will encompass both anode and cathode developments. Cathode materials including high-energy and/or high voltage mixed metal oxides will be considered together with anode materials, including graphite, silicon and lithium titanate.