ACCELERATED RELIABILITY TESTING OF ELECTRIC VEHICLES
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Performance Safety and Abuse Test This test as the name suggests, characterizes the response of integrated battery systems to expected and worse-case accident and abuse situations. The information gained from these tests is used to qualify the vehicles as safe operating and accident/crash worthy.
ACCELERATED RELIABILITY TESTING OF ELECTRIC VEHICLES Accelerated reliability tests of EVs are performed to provide several years of vehicle performance information in a short time—within a year. The tests are based on standard guidelines and the results of the tests provide a better understanding of EV performance. These tests are conducted by operating the EVs in accelerated mileage modes that simulate typical fleet missions with the intent to obtain and analyze vehicle operation experiences within a relatively short period of one year. While these tests are conducted in an accelerated mode, they are always performed within the EV manufacturer’s guidelines and do not void the manufacturer’s warranty under any circumstances. In case the vehicle battery pack cannot be charged using a fast charge mode, the tests will be performed in accordance with no fast charging. Each vehicle under the reliability test is tested for a period of one year. The vehicle is required to maintain the original components for the entire 25,000 miles testing period. The accelerated reliability tests may be carried out beyond the one-year period to gain additional vehicle knowledge. The miles driven during the trip should be approximately 100 miles per day. Each driving cycle should be balanced with respect to the time required to charge so that the vehicle can be ready for the next test trip. The battery pack should not be discharged beyond 80% DOD unless recommended by the battery manufacturer. During the test, it is important to maintain the battery pack at 80% DOD. The data gathered during the tests include: • • •
Average miles/charge by vehicle model (including potential range) Miles/charge by vehicle model (on a monthly or quarterly basis) Cumulative fleet mileage (on a monthly basis)
The charging pattern indicates when the vehicle is charged (time of the day), the duration of the charge (hours), and the magnitude of the charge (kWhr). In addition, the charging pattern also provides an
