UN38.3 Standard Testing Items & Procedures
The UN38.3 standard includes the following 8 detection items:
- T1 low pressure,
- T2 temperature cycle,
- T3 vibration,
- T4 shock,
- T5 external short circuit,
- T6 heavy object impact (lithium battery core),
- T7 overcharge (lithium battery or lithium battery )
- T8 forced discharge (lithium battery cells).
For lithium batteries or lithium battery packs, a total of 7 items of tests T1 → T5, T6, and T7 are required. However, for lithium battery cells, T1 → T5, T6 and T8 tests are required. Among them, T6, T7, and T8 tests need to use separate samples. And T1 → T5 test sequentially test the same sample.
Comparison of UN38.3 & International Standards
Compared with other international lithium battery standards, the temperature cycling conditions specified in the UN38.3 standard are more demanding and longer. Other international standard test items generally use separate samples for testing. However, the T1 → T5 test in the UN3813 standard tests the same sample in sequence. The previous test may have a negative impact on the next test, resulting in failure to pass the test. If the lithium battery submitted for inspection is tested for T1 → T5 in the UN 38.3 standard, there will be one item unqualified. Enterprises need to re-test UN3813 standard after process improvement, which will greatly extend the testing cycle.
It can be known from Table 1 that compared with the international standard IEC62133, the high and low temperature exposure time of the temperature cycling item in the UN3813 standard is up to 6 hours, and the low temperature test temperature is -40 ± 2 ° C. The temperature cycle of the temperature cycle test is larger and the test cycle is longer. It is easier to cause the internal materials of the battery cell to decompose and generate gas. In the case of problems in the production process, when the gas generated during the temperature shock reaches a certain pressure, the gas is likely to leak from the weak point of the battery case or the internal seal, resulting in substandard phenomena such as gas leakage and liquid leakage.
More details: https://belltestchamber.com/un38-3-standard-requirements-for-lithium-battery-production.html