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The U.S. Army has been pursuing vehicle electrification to achieve enhanced combat effectiveness. The benefits include new capabilities that require high power pulse duty cycles. However as the vehicle platform size decreases, the Energy Storage System (ESS) pulse power discharge rates (> 40 C rate) to support system requirements can be significantly greater than commercial ESS. Results are reported of high power pulse duty cycles on lithium iron phosphate cells that show a dramatic loss in lifetime performance. For a 2 s and 3 s pulse duration tests, the observed degradation is 22 % and 32 % respectively. Although these cells were thermally managed in a convective chamber at 10°C, the 2 s pulse showed a 31°C temperature rise and the 3 s pulse, a 48°C temperature rise. The decreased lifetime is attributed to increased lithium loss due to the increased temperature during pulse discharging.

Fuel cell vehicle fuel consumption measurement is considerably different from internal combustion engine vehicle fuel consumption measurement. Conventional Carbon Balance Method and Flow Measurement methods for gas consumption within combustion engines are not suitable for fuel cell vehicles. The small quantities of fuel consumed and the characteristics of hydrogen itself impose a challenge for the hydrogen measurement. This paper addresses fuel consumption measurement for fuel cell vehicles using various methods such as mass flow measurement, pressure/temperature/volume method, weigh method as well as other methods. The advantages and disadvantages of these methods are discussed.

Hydrogen Fuel cell vehicles, and techniques for fuel economy measurement and fuel economy calculations are considerably different from those traditionally used fro combustion engine vehicles.. Like gasoline or diesel hybrid vehicles, fuel cell vehicles typically use batteries or other power systems such as super-capacitors for load leveling. Thus, the energy transfer or consumption from these supplemental power sources to the drive train should be compensated for when determining fuel consumption or fuel economy. This paper addresses fuel economy calculations and testing for hybrid hydrogen fuel cell vehicles. The impact of supplemental power systems to a fuel cell vehicle's fuel economy and the various methods to derive actual vehicle fuel economy with supplemental power system usage are discussed.

Solid-state lithium-ion batteries that use a solid electrolyte may potentially operate at wide temperatures and provide satisfactory safety. Moreover, the use of a solid electrolyte, which blocks the formation of lithium dendrites, allows batteries to use metallic lithium for the anode, enabling the batteries gain an energy density significantly higher than that of traditional lithium-ion batteries. Solid electrolytes play a role of conducting lithium ions and are the core of solid-state lithium-ion batteries. However, the development of solid lithium electrolytes towards a high lithium ionic conductivity, good chemical and electrochemical stability and scalable manufacturing method has been challenging. We report a new material composed of nitrogen-doped lithium metaphosphate, denoted as NLiPO3.