T2. Thermal Test (การทดสอบภายใต้วัฏจักรอุณหภูมิ)

Test procedure
   Test cells and batteries are to be stored for at least six hours at a test temperature equal to 72 ± 2°C, followed by storage for at least six hours at a test temperature equal to - 40 ± 2 °C . The maximum time interval between test temperature extremes is 30 minutes, after which all test cells and batteries are to be stored for 24 hours at ambient temperature (20 ± 5°C). For large cells and batteries, the duration of exposure to the test temperature extremes should be at least 12 hours.

Requirement
   Cells and batteries meet this requirement if there is no leakage, no venting, no disassembly, no rupture and no fire and if the open circuit voltage of each test cell or battery after testing is not less than 90% of its voltage immediately prior to this procedure. The requirement relating to voltage is not applicable to test cells and batteries at fully discharged states.