Evaluation of Electric Vehicles as an Alternative for Work Trip and ...

95 Ah ALAB delivered 79 cycles during its lifespan, but only sixteen
full-capacity cycles were experienced before the first 10% loss in
battery-capacity occurred.
As a result of the progressive battery failures that occurred
during the spring and summer of 1996, which resulted in diminishing
range, the car was removed from commuter service for repairs. Because
the car was not working properly during the commuter evaluation, it was
not provided to the Consumers Union automobile testing facility in
Moodus for their evaluation in 1996. The evaluation of the ALAB car was
suspended on July 29, 1996. The vehicle was towed to an EV specialist
on October 3, 1996. Data from all battery cycles had been recorded and
was provided to the EV specialist, EV manufacturer, Rideshare, and the
battery company for their analyses. July 1996 was also the last month
data was transmitted by Rideshare to DARPA under the CCEVD project, as
this project was now completed.
Six problem areas were identified that contributed to failure in
the ALAB car. Problems were identified with wiring and electrical
components that required repair. Three of the thirteen batteries were
found to be mounted incorrectly, which was thought to have lead to
internal damage from road shocks. The battery manufacturer identified
errors in pre- and post-delivery battery cycling procedures, principally
associated with battery overcharging. The car manufacturer and
researchers had followed the manufacturer’s recommendation that the ALAB
car be plugged in whenever the car was parked, i.e., at every
opportunity. What was not known was that recharging after short drives
was resulting in overcharging, which damaged the cells due to battery
gassing. Pre-delivery test-drives by the car manufacturer may have been
too short between recharges. New procedures were recommended by the
battery manufacturer that established a minimal battery depth-of-
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