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Track and dynamometer testing of the Eaton Dual Shaft Electric Propulsion (DSEP) minivan has been performed by the Idaho National Engineering Laboratory (INEL). The dynamometer testing included constant speed tests up to 88 km/h and driving cycle tests on the SAE J227a C and D cycles and the Federal Urban Driving Schedule (FUDS) as well as maximum effort acceleration tests. The dynamometer data were analyzed to determine the energy consumption (Wh/km) of the DSEP vehicle for the various driving modes and to project the range of the vehicle if the NiF170 nickel-iron battery had been at its rated capacity. Ranges of 90-125 miles at constant speeds and about 70 miles on the driving cycles were projected. Comparisons were made of the performance of the DSEP vehicle and the ETX-II and the TEVan minivans, which have been developed on other DOE and EPRI programs using lead-acid, nickel-iron, nickel-cadmium, and sodium-sulfur batteries.

Field experience with electric vehicles has shown in a significant number of cases, the performance of the batteries starts to degrade in a few months or a few thousand miles resulting in unhappy vehicle owners. This has occurred even for batteries for which the manufacturer has claimed a cycle life of several hundred deep discharge cycles. In this paper, the reasons are explored for this large difference between the expected and experienced battery cycle life and what life cycle testing should be done to greatly reduce the uncertainty in battery pack life. Test procedures for battery life testing are discussed and it is shown that there is a large difference in the cycle life that would be inferred from test results for one or two modules compared to that from testing a pack of many modules (at least ten).

Series of designs of compact and full-size passenger cars and minvans were formulated using state-of-the-art electric driveline components and battery modules/cells. The performance of each of the designs was simulated using the ELVEC. Computer runs were made for constant speeds between 40 and 88.5 km/h and the J227D and FUDS driving cycles as well as maximum effort accelerations. The simulations indicated for the three vehicle types the target ranges and acceleration times could be met for both the near-production and advanced batteries. The targets were consistent with those established for the various batteries by the DOE Battery Goals Task Force in 1988. The energy consumption values calculated for vehicles utilizing DC drivelines were consistently lower by 15-25% than those for vehicles using AC drivelines primarily due to the higher efficiency of the transmission in the DC power-train system.