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This work will present the development of a Modular High Voltage Standardization suitable for US ARMY Ground Vehicles. The standardization is in support of the Army’s Modernization Strategy focus on Next Generation Combat Vehicle (NGCV). GVSC with Department of Defense partners (OECIF, NAVY) is leading the development of this High-Voltage (HV) Specification for Energy Storage Modules (ESMs), i.e. Li-ion batteries. Based on the operational requirements for ARMY platforms to operate in austere environments with no fixed charging infrastructure, it is anticipated that Hybrid Electric Vehicles would be the initial users of an ESM. Greater penetration of safe, low cost ESM in support of electrification will result in improved platform survivability, maneuverability and capability.

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.

Modern commercial and military vehicles are equipped with more electrical accessories and demand more power than ever before. This causes an increase in the weight of the battery as well as drives the battery to end of life when the vehicle is stationary with the engine off. Lithium ion batteries, which are known for their high power and energy to weight density, long cycle life, and low self-discharge rate, are considered to be an alternative for the replacement of existing Starting, Lighting, and Ignition (SLI) lead acid batteries. Lithium ion battery chemistry offers double the reserve time of the stock battery and a significantly greater number of charging and discharging cycles while providing weight savings. There is no acid inside a lithium ion battery to cause corrosion, which eliminates potential damage to a vehicle from chemical spills and poisonous gases.