Short answer: GB 38031-2025 is China’s mandatory safety standard for electric-vehicle traction batteries. It replaced GB 38031-2020 and has applied to new vehicle type approvals since 1 July 2026. The biggest change is in the thermal propagation test: the battery pack must not catch fire or explode after a cell goes into thermal runaway, and smoke must not harm occupants. The old rule only required a warning 5 minutes before fire or explosion.
Key facts
| Item | Detail |
|---|---|
| Full title (Chinese) | 电动汽车用动力蓄电池安全要求 |
| Replaces | GB 38031-2020 |
| Published | 2025 (sources give different dates between March and May 2025; check the official notice) |
| New type approvals | Requirements apply from 1 July 2026 |
| Existing approved types | Reported compliance deadline of 1 July 2027 (confirm against the official notice) |
| Scope | Lithium-ion and nickel-metal-hydride traction batteries for electric vehicles: cells, packs and systems |
| Test count | 7 cell-level tests and 17 pack/system-level tests, as reported by Xinhua |
What changed from GB 38031-2020
- Thermal propagation: from “warn” to “no fire, no explosion”. The 2020 edition required an alarm at least 5 minutes before fire or explosion, so that occupants could get out. The 2025 edition requires that the pack does not catch fire or explode after thermal runaway of a cell. An alarm is still required, and smoke must not harm occupants. Some industry articles report an observation period of 2 hours and a temperature limit at monitoring points. We have not confirmed these figures against the official text, so check the standard itself.
- New bottom-impact test, representing damage from road debris or grounding.
- New post-fast-charge safety test. After a series of fast-charge cycles (reported as 300), the battery must pass an external short-circuit test without fire or explosion.
What it means for barrier and fire-protection materials
- Barriers now carry the pass/fail result. Under the old rule, a pack could pass if it warned in time. Under the new rule, propagation inside the pack must be stopped or contained, which raises demand for cell-to-cell barriers, pack-lid fire shields and venting paths.
- Designs must cope with the worst case. The test can trigger the cell that is hardest to protect, so barrier thickness and material choice are set by the worst position in the pack, not the average.
- Ageing matters. Because fast-charge cycling is now part of the test sequence, barrier materials that lose thickness or crack under repeated cell swelling are a risk.
- Exporters are affected too. Chinese cell and pack makers supplying global OEMs often use one design across markets, so this rule is shaping barrier design well beyond China.
Sources
- Xinhua via Beijing News, "电动汽车电池新国标7月落地，安全门槛再升级" (29 June 2026): bjnews.com.cn
- China Securities Journal (3 July 2026): cs.com.cn
- MPR China Certification, "New battery certification standard GB38031-2025 replaces previous regulation": china-certification.com
- CarNewsChina (27 December 2025): carnewschina.com
- Official text: National Public Service Platform for Standards Information, std.samr.gov.cn (search "GB 38031-2025")