Evaluating Polyolefin Separator Friction Limits in Lubricated Cell Stacks
Sufficient stack pre-load retention and ceramic coating friction prevent wetted polyolefin separator sliding and tab shear in lubricated cell stacks.
UN 38.3 Section 38.3.4.3
Meaning
Safety testing requirements define the vibration profile that lithium batteries must withstand for international transport. Compliance with un 38.3 section 38.3.4.3 ensures that cells and batteries do not leak, vent, catch fire or rupture when subjected to a range of frequencies. The test simulates the mechanical stresses encountered during air and sea shipping.
Vibration Profile
Equipment subjects the samples to a sinusoidal waveform that sweeps between 7 and 200 hertz over several hours. During the execution of un 38.3 section 38.3.4.3, the peak acceleration reaches 8G for large batteries and 2G for small ones. This movement tests the mechanical integrity of the internal connections.
Shakers apply the vibration in three mutually perpendicular directions to cover all possible orientations.
Pass Condition
Observations after the test confirm that the open circuit voltage remains stable and the casing shows no signs of physical damage. Meeting the requirements of un 38.3 section 38.3.4.3 is a legal prerequisite for the commercial distribution of battery products. Any mass loss or leakage results in a failure of the certification.
Regulatory Scope
International shipping laws mandate these tests for all lithium-based energy storage devices. un 38.3 section 38.3.4.3 forms part of a larger suite of tests covering altitude, thermal shock, impact and short circuit.