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U.S. Department of Energy
Office of Scientific and Technical Information

Single-shaft electric propulsion system technology development program -- ETX-II

Technical Report ·
OSTI ID:7030951

In 1981, discussions between Ford and General Electric (GE) evolved a concept for an advanced electric vehicle powertrain, which was subsequently presented to the US Department of Energy (DOE) as an unsolicited proposal. The concept involved a combination of technology from Ford and GE that would result in a unique powertrain based on a motor and transmission concentric with the drive wheel axis. Initial work suggested that the entire motor/transaxle combination could be expected to be smaller and lighter than the direct current (dc) motors that were in use in electric vehicles at that time and that the powertrain could be expected to be more efficient than other available powertrains. This program (ETX-I) was awarded to Ford Motor Company and it was established that the most likely first introduction of an electric vehicle would be in the form of a fleet of small commercial vans. The ETX-II propulsion system concept was aimed at advancing the technology through improving the size, weight, efficiency, reliability, and cost characteristics of the ETX-I powertrain and by integrating advanced battery technologies compatible with the powertrain to form a complete propulsion system. Unique developments for the ETX-II program included the transaxle, a two-speed automatic transmission and three-phase interior permanent magnet alternating current (ac) motor on a common axis integrated with the rear axle of the test bed van; The traction battery selected for this propulsion system was the sodium-sulfur battery. This was the only advanced technology that had been developed to a point that would allow the test vehicle to have a range of over 160 kilometers (100 miles) without the battery exceeding 25% of the vehicle's gross weight.

Research Organization:
Ford Motor Co., Dearborn, MI (United States). Research Staff; General Electric Co., Schenectady, NY (United States). Corporate Research and Development Center
Sponsoring Organization:
DOE; USDOE, Washington, DC (United States)
DOE Contract Number:
AC07-85NV10418
OSTI ID:
7030951
Report Number(s):
DOE/NV/10418-3; ON: DE92019410
Country of Publication:
United States
Language:
English