GB 18384-2025 and GB 38031-2025: what changed for EV high-voltage safety
Two mandatory Chinese standards took effect on 1 July 2026. Battery packs must now not catch fire or explode after thermal runaway, and vehicles need a physical high-voltage disconnect.
- 01Both standards have applied to new type approvals since 1 July 2026.
- 02Already-approved vehicle types must comply by 1 July 2027.
- 03Battery packs: no fire and no explosion after thermal runaway, instead of a 5-minute warning.
- 04New battery tests: bottom impact and short circuit after 300 fast-charge cycles.
- 05Vehicles: a physical one-button high-voltage disconnect and new underbody tests.
Two standards, one date
| Standard | Scope | Replaces | Applies from |
|---|---|---|---|
| GB 18384-2025 | Electric vehicle safety (whole vehicle) | GB 18384-2020 | 1 Jul 2026 |
| GB 38031-2025 | Traction battery safety | GB 38031-2020 | 1 Jul 2026 |
New type approvals must comply from 1 July 2026. Vehicle types approved earlier have until 1 July 2027.
GB 38031-2025: from warning to prevention
Thermal propagation
The 2020 edition required a warning at least five minutes before a fire or explosion, so occupants could leave. The 2025 edition goes further: after thermal runaway of a cell, the pack must not catch fire or explode during the observation period, and smoke must not harm occupants. The warning signal is still required.
Bottom impact
A new test strikes the underside of the pack with a steel ball to simulate stones and debris. After the test there must be no electrolyte leakage, no fire and no explosion, and insulation must still be acceptable.
Safety after fast charging
Cells and packs are cycled with repeated fast charging, then subjected to an external short-circuit test. The pack must not catch fire or explode. Fast charging is now part of the safety assessment, not only the performance assessment.
GB 18384-2025: vehicle-level changes
- Physical high-voltage disconnect. A dedicated button must be able to cut the high-voltage circuit independently of the vehicle software, so it still works after a crash, a system fault or a thermal event.
- Underbody tests. New scraping and impact scenarios represent hitting kerbs, stones and debris from below.
- Thermal events at vehicle level are judged with the same logic as the battery standard: no fire, no explosion, no harmful smoke in the cabin.
- Event data recording of safety-relevant high-voltage data.
What this means for testing
The changes move work earlier in the programme. Pack designs need fire-barrier and venting concepts validated before the type-approval test, and fast-charging profiles now affect safety results. Suppliers of high-voltage parts (connectors, contactors, cables, on-board chargers) should expect stricter insulation and protection requirements from vehicle makers.
Our partner laboratory network covers high-voltage component testing, insulation and protection checks, and EMC for EV systems.
FAQ
Do vehicles already on the road need to be modified?
No. The standards apply to vehicle type approvals. New types from 1 July 2026, already-approved types by 1 July 2027.
Is the thermal-runaway warning still required?
Yes. The warning remains, but the pack must also not catch fire or explode.
Are these standards mandatory?
Yes. Both are mandatory national standards (GB, not GB/T).
