Information date: 11 November 2026 — GB 38031-2025, the new edition of China’s traction-battery safety standard for electric vehicles, was published by SAMR and the standardisation administration in 2025, replacing GB 38031-2020, and applies to new type approvals from 1 July 2026. The substantive change is the thermal-propagation requirement: instead of giving occupants a warning window before fire, the new text requires that after a thermal event is triggered the battery system must not catch fire and must not explode, observed over a defined post-trigger period. It adds a bottom-impact test on the pack, a fast-charge cycling test, and tighter requirements on insulation resistance and on system behaviour when a single cell vents. For a foreign OEM assembling packs in China, the pack rather than the vehicle is the object under test. Decide early. If your China programme targets a 2026 or later type approval, design to the 2025 edition now and avoid spending on 2020-edition re-testing. If you hold an existing 2020-edition report and launch before the application date, confirm with the approval authority whether it still supports approval in the transition window. If the pack uses imported cells, lock the cell supply contract before testing, because a cell change afterwards restarts the file. If volumes are low, buy a pack from a licensed domestic supplier and rely on its report rather than building test capability. If you assemble locally, add the re-certification trigger list to the engineering change process.
Verified facts and scope
GB 38031-2025, the new edition of China’s traction-battery safety standard for electric vehicles, was published by SAMR and the standardisation administration in 2025, replacing GB 38031-2020, and applies to new type approvals from 1 July 2026. The substantive change is the thermal-propagation requirement: instead of giving occupants a warning window before fire, the new text requires that after a thermal event is triggered the battery system must not catch fire and must not explode, observed over a defined post-trigger period. It adds a bottom-impact test on the pack, a fast-charge cycling test, and tighter requirements on insulation resistance and on system behaviour when a single cell vents. For a foreign OEM assembling packs in China, the pack rather than the vehicle is the object under test.
Scope has to be fixed before the numbers mean anything: Applies to the traction battery pack of battery-electric vehicles sold or type-approved in China, whether the pack is imported complete, assembled from imported cells, or built locally with local cells. Confirm before planning: which entity holds the type approval, the OEM, the joint venture or the pack supplier; whether existing pack test reports were produced to the 2020 edition and how they fare under the new approval; whether cells and the battery management system count as part of the tested system; whether a separate certificate is needed for the same pack sold as a replacement part; and how far ahead the accredited test houses are booked, since every domestic OEM is re-testing on the same timetable. Anything outside that set is a separate question with its own evidence requirement, and mixing the two is the most common way a workable plan turns into an unusable one.
For a decision on “Guide: GB 38031-2025 and the Battery Pack a Foreign OEM Wants to Assemble in China — the Thermal-Propagation Test, the No-Fire Requirement and the Re-Certification File”, keep three layers apart: the published rule or statistic, the company’s own orders and process records, and the assumptions nobody has tested yet. The first layer defines the external conditions, the second proves what is true for this business, and the third is where the risk actually sits. Public material cannot substitute for a contract, a system log, a sample or a live test.
A practical way to test the scope is to ask which parts of “Guide: GB 38031-2025 and the Battery Pack a Foreign OEM Wants to Assemble in China — the Thermal-Propagation Test, the No-Fire Requirement and the Re-Certification File” would still be true if the company changed supplier, entity or product line tomorrow. Items that survive that change belong to the rule layer and can be taken from official publications; items that do not survive belong to the operating layer and have to be rebuilt from invoices, warehouse records, customs entries or platform statements. Where Applies to the traction battery pack of battery-electric vehicles sold or type-approved in China, whether the pack is imported complete, assembled from imported cells, or built locally with local cells. Confirm before planning: which entity holds the type approval, the OEM, the joint venture or the pack supplier; whether existing pack test reports were produced to the 2020 edition and how they fare under the new approval; whether cells and the battery management system count as part of the tested system; whether a separate certificate is needed for the same pack sold as a replacement part; and how far ahead the accredited test houses are booked, since every domestic OEM is re-testing on the same timetable, the two layers are frequently mistaken for each other, and an action plan built on the wrong one either over-complies or misses a deadline it never saw coming.
How the effect reaches operations
The standard is a mandatory national standard, so compliance is a precondition of type approval rather than a marketing claim. Moving to a no-fire outcome transfers the engineering burden from warning the driver to preventing propagation, which pushes requirements down into cell chemistry, separator design, venting geometry, pack-level thermal barriers and detection speed in the management system. Because the propagation test is destructive and configuration-specific, any change of cell supplier, module layout or enclosure invalidates the report. The re-certification file therefore behaves like an engineering change control document: it must show that the tested configuration is the production configuration, and it must be re-run whenever that configuration moves, which is where programme schedules usually break.
Typical misjudgements: assuming a pack tested to the 2020 edition stays valid for a 2026 approval; sourcing cells from one supplier for the test and another for series production; treating a UN 38.3 transport test as evidence of pack safety, which it is not; and under-budgeting test hardware, since propagation tests destroy complete packs and several variants are usually needed. There is schedule risk as well, because accredited laboratories are capacity-constrained and a single failed propagation test pushes the programme back by a full rebuild cycle. Finally, a pack certified abroad to an equivalent standard does not satisfy a Chinese mandatory standard; the Chinese test must be performed, normally on Chinese equipment with a witnessed report.
Translated into an operating sequence, The standard is a mandatory national standard, so compliance is a precondition of type approval rather than a marketing claim. Moving to a no-fire outcome transfers the engineering burden from warning the driver to preventing propagation, which pushes requirements down into cell chemistry, separator design, venting geometry, pack-level thermal barriers and detection speed in the management system. Because the propagation test is destructive and configuration-specific, any change of cell supplier, module layout or enclosure invalidates the report. The re-certification file therefore behaves like an engineering change control document: it must show that the tested configuration is the production configuration, and it must be re-run whenever that configuration moves, which is where programme schedules usually break. That ordering matters: check applicability first, then the transmission step, and only then the size of the gap in cost or timing. When an intermediate step cannot be confirmed, the honest response is to narrow the scope of the conclusion rather than to substitute an industry average for the company’s own figures.
The cost of getting the order wrong is asymmetric. A team that checks applicability too late usually discovers it at the point where the shipment, the filing or the invoice can no longer be changed without penalty, and by then the only remaining lever is price. A team that checks early spends a few hours on questions that turn out to be irrelevant, which is cheap by comparison. On “Guide: GB 38031-2025 and the Battery Pack a Foreign OEM Wants to Assemble in China — the Thermal-Propagation Test, the No-Fire Requirement and the Re-Certification File” the practical rule is therefore to spend the first hour on scope and the second on the numbers, never the other way round.
Decision
Decide early. If your China programme targets a 2026 or later type approval, design to the 2025 edition now and avoid spending on 2020-edition re-testing. If you hold an existing 2020-edition report and launch before the application date, confirm with the approval authority whether it still supports approval in the transition window. If the pack uses imported cells, lock the cell supply contract before testing, because a cell change afterwards restarts the file. If volumes are low, buy a pack from a licensed domestic supplier and rely on its report rather than building test capability. If you assemble locally, add the re-certification trigger list to the engineering change process.
The conditions should be written down so the decision can be re-run by someone else: Applies to the traction battery pack of battery-electric vehicles sold or type-approved in China, whether the pack is imported complete, assembled from imported cells, or built locally with local cells. Confirm before planning: which entity holds the type approval, the OEM, the joint venture or the pack supplier; whether existing pack test reports were produced to the 2020 edition and how they fare under the new approval; whether cells and the battery management system count as part of the tested system; whether a separate certificate is needed for the same pack sold as a replacement part; and how far ahead the accredited test houses are booked, since every domestic OEM is re-testing on the same timetable. When those hold, proceed as described; when one is missing, close the gap first and decide afterwards. Descriptive summary of a Chinese mandatory standard. Test protocols, tolerances and transition dates must be read from the published standard text and the issuing authorities’ notices. This is not a certification, a test report or a legal opinion.
Two workstreams usually have to move in parallel. The compliance workstream closes the document side of “Guide: GB 38031-2025 and the Battery Pack a Foreign OEM Wants to Assemble in China — the Thermal-Propagation Test, the No-Fire Requirement and the Re-Certification File” — registrations, confirmations, filings — while the commercial workstream protects the delivery date, the pricing already quoted and the customer commitments that were made on the earlier reading of the rules. Running them as one queue is how small documentation gaps become missed shipment dates: the commercial side waits for a certificate that could have been requested a week earlier. Decide early. If your China programme targets a 2026 or later type approval, design to the 2025 edition now and avoid spending on 2020-edition re-testing. If you hold an existing 2020-edition report and launch before the application date, confirm with the approval authority whether it still supports approval in the transition window. If the pack uses imported cells, lock the cell supply contract before testing, because a cell change afterwards restarts the file. If volumes are low, buy a pack from a licensed domestic supplier and rely on its report rather than building test capability. If you assemble locally, add the re-certification trigger list to the engineering change process. Set one owner per workstream and one shared status sheet, and treat a red item on either side as a reason to freeze only the affected order.
Implementation checklist
- Map every pack variant to a tested configuration and flag any cell or enclosure change.
- Book destructive propagation tests early and assume at least one failure and rebuild.
- Freeze the production bill of materials against the tested pack before type approval.
- Name one decision owner, one execution owner and one review date.
- Keep the source page, access date, entity and internal evidence.
- On any change, reopen only the affected judgement.
Evidence and review
Start with the smallest test that can change the answer: Map every pack variant to a tested configuration and flag any cell or enclosure change. Pick one real entity or one representative case, write down the continue, watch and stop conditions in advance, and record the input version, the owner, the start time and the actual result. The first pass should only look at facts that move the decision; formatting preferences are not risk.
The second pass is completed by “Book destructive propagation tests early and assume at least one failure and rebuild”, and someone who did not prepare the file should spot-check one piece of critical evidence. Typical misjudgements: assuming a pack tested to the 2020 edition stays valid for a 2026 approval; sourcing cells from one supplier for the test and another for series production; treating a UN 38.3 transport test as evidence of pack safety, which it is not; and under-budgeting test hardware, since propagation tests destroy complete packs and several variants are usually needed. There is schedule risk as well, because accredited laboratories are capacity-constrained and a single failed propagation test pushes the programme back by a full rebuild cycle. Finally, a pack certified abroad to an equivalent standard does not satisfy a Chinese mandatory standard; the Chinese test must be performed, normally on Chinese equipment with a witnessed report. A single small deviation can be corrected in place; a repeated deviation, or one that touches a statutory duty or changes the economics, is what justifies pausing the affected part.
After “Freeze the production bill of materials against the tested pack before type approval”, compare the actual result with the baseline rather than with the impression of the team. Decide early. If your China programme targets a 2026 or later type approval, design to the 2025 edition now and avoid spending on 2020-edition re-testing. If you hold an existing 2020-edition report and launch before the application date, confirm with the approval authority whether it still supports approval in the transition window. If the pack uses imported cells, lock the cell supply contract before testing, because a cell change afterwards restarts the file. If volumes are low, buy a pack from a licensed domestic supplier and rely on its report rather than building test capability. If you assemble locally, add the re-certification trigger list to the engineering change process. When the arrangement is extended to more products, customers or processes, keep the same success test and one complete record per batch. If later information changes, update only the affected fields.
One last discipline keeps the file usable next quarter: write the closing note as if a colleague who has never spoken to the supplier has to act on it. That note states what was verified, on which date, against which source, and what remains open — on “Guide: GB 38031-2025 and the Battery Pack a Foreign OEM Wants to Assemble in China — the Thermal-Propagation Test, the No-Fire Requirement and the Re-Certification File” it also states which of the three actions was actually finished and which was only scheduled. Teams that skip the closing note re-litigate the same question every month, and each round costs more than the documentation would have. Descriptive summary of a Chinese mandatory standard. Test protocols, tolerances and transition dates must be read from the published standard text and the issuing authorities’ notices. This is not a certification, a test report or a legal opinion.
Limits of the conclusion
Descriptive summary of a Chinese mandatory standard. Test protocols, tolerances and transition dates must be read from the published standard text and the issuing authorities’ notices. This is not a certification, a test report or a legal opinion.
The limits are structural rather than cautious wording. Public sources describe rules and market conditions; they do not observe “Guide: GB 38031-2025 and the Battery Pack a Foreign OEM Wants to Assemble in China — the Thermal-Propagation Test, the No-Fire Requirement and the Re-Certification File” inside a specific company. Where the analysis quotes a second-hand interpretation, the original release has to remain reachable, and a figure that cannot be traced back does not enter the decision table. Where the point depends on Applies to the traction battery pack of battery-electric vehicles sold or type-approved in China, whether the pack is imported complete, assembled from imported cells, or built locally with local cells. Confirm before planning: which entity holds the type approval, the OEM, the joint venture or the pack supplier; whether existing pack test reports were produced to the 2020 edition and how they fare under the new approval; whether cells and the battery management system count as part of the tested system; whether a separate certificate is needed for the same pack sold as a replacement part; and how far ahead the accredited test houses are booked, since every domestic OEM is re-testing on the same timetable, the conclusion is only as current as the last check of those conditions.
