Cell-level tests (Section 8.1)

The seven safety tests applied to individual battery cells under GB 38031-2025. All cell tests share the same pass criterion family — the cell shall not catch fire or explode (clause 5.1.x). There is no insulation, leakage, or housing-crack requirement at cell level. All cell tests use a 1 h observation period at test environment temperature (22 °C ± 5 °C).

#	Clause	Test	Status vs. 2020	One-line summary
1	8.1.2	Over-discharge	revised (method)	Discharge at I1 for 30 min starting from the discharge termination voltage.
2	8.1.3	Overcharge	unchanged	Continue charging at ≥ I3 to 1.1× termination voltage or 115 % SOC.
3	8.1.4	External short-circuit	unchanged	Short positive↔negative through < 5 mΩ for 10 min.
4	8.1.5	Heating	revised (method)	Ramp 5 °C/min to 130 °C / hold 30 min (NiMH: 85 °C / 2 h).
5	8.1.6	Temperature cycling	unchanged	Five 8 h cycles between −40 °C and 85 °C per Table 1.
6	8.1.7	Compression (extrusion)	revised (method)	75 mm semi-cylindrical plate, ≤ 2 mm/s, stop at V = 0 / 15 % / 100 kN / 1000× mass.
7	8.1.8	Safety after fast-charge cycles	new	300 cycles of 20→80 % SOC in ≤ 15 min, then run the 8.1.4 external short.

For the equivalent pack/system tests, see Pack & system tests. For the full at-a-glance table covering all 24 tests, see All tests at a glance.