Lithium cell transport and safety documentation
What has to travel with a lithium cell shipment, which standard covers what, and how to tell whether a certificate actually covers the model you are buying.
Two different questions get confused constantly. Transport rules ask whether a consignment may move, and in what configuration. Product safety standards ask whether a cell design is safe in use. A shipment can satisfy the first and the product still fail the second, because they are assessed by different bodies against different documents.
UN38.3 — the transport test, and what it is not
UN38.3 is the test series in the UN Manual of Tests and Criteria that a lithium cell or battery must pass before it may be offered for transport. It covers eight tests: altitude simulation, thermal cycling, vibration, shock, external short circuit, impact or crush, overcharge, and forced discharge. Every one of them has to pass on the same design.
What the buyer receives is the test summary, not the full laboratory report. The summary identifies the cell, the tested construction, and the tests passed. It is a transport document: it says nothing about cycle life, capacity retention, or whether the cell is suitable for your application.
The common misreading
A UN38.3 summary is not a safety certificate for the product you are building. It is the document that lets the cells travel to you. Product safety for the end application is a separate standard (see below).
The three transport entries that are not interchangeable
| Configuration | UN number | What it covers |
|---|---|---|
| Cells or batteries alone | UN3480 | Loose cells and battery packs shipped on their own |
| Packed with equipment | UN3481 | Batteries in the same package as the device but not installed |
| Contained in equipment | UN3091 / UN3481 | Batteries installed in the device being shipped |
Which entry applies is decided by the shipping configuration, not by the product. Repacking cells into a different configuration can change the entry and therefore the paperwork.
For air transport, standalone lithium-ion cells and batteries are additionally limited in state of charge — commonly 30% — and the applicable packing instruction changes with the configuration and the net quantity per package. This is one of the areas where the airline and the freight forwarder have the final word, and where a supplier who ships cells regularly will already know the current edition.
IEC 62133-2 — safety for portable applications
IEC 62133-2 is the safety standard for sealed portable secondary lithium cells and batteries. It is the reference used for consumer and portable product certification in most markets outside North America, and it is assessed on the cell and on the battery assembly, not on the shipment.
The practical difference from UN38.3 is intent: UN38.3 asks whether the cell survives transport abuse, IEC 62133-2 asks whether it is safe in normal use and reasonable misuse. A cell can hold a valid UN38.3 summary and still need IEC 62133-2 assessment before a product can carry a CE mark.
IEC 62619 — industrial and stationary
IEC 62619 applies to secondary lithium cells and batteries for industrial applications, including stationary energy storage. If the pack is going into an ESS, a UPS or industrial equipment, this is usually the applicable safety standard rather than IEC 62133-2. It also addresses functional safety of the battery management system, which IEC 62133-2 does not.
The distinction matters commercially: a storage customer asking for "the safety certificate" usually means IEC 62619, and a supplier who only holds IEC 62133-2 is answering a different question.
UL 1642 and UL 2054 — North America
UL 1642 covers lithium cells; UL 2054 covers battery packs. Recognition is issued under a file number, and the file lists the constructions and models covered. The only meaningful check is whether your model designation appears in that file — "the supplier has a UL certificate" is not a claim about your cell.
A file number that covers a family does not automatically cover a variant added later. When a manufacturer adds a model, the file is updated; until it is, the earlier document is accurate about the earlier list and silent about the new part.
MSDS, and why the configuration has to match
The safety data sheet describes the hazards of the article as shipped. Its transport classification section has to match the actual configuration: cells, batteries, and batteries contained in equipment carry different entries and different quantities. A data sheet written for loose cells does not correctly describe a pack installed in a device.
This is also why a consignment can be held at a port even with valid documents in hand — the documents describe a configuration the forwarder is not actually looking at.
How to verify a certificate in five minutes
- Read the model designation on the certificate and compare it character by character with the marking on the cells. Suffix differences matter.
- Check the chemistry and construction described — a certificate for a different chemistry does not transfer.
- Check the standard revision named on the document, and whether that revision is the one your market currently accepts.
- Check the certificate holder. It should be the manufacturer, or the entity that actually holds the approval, not a distributor.
- Check the scope statement for exclusions. Many certificates list models covered *and* models explicitly not covered.
If any of the five cannot be answered from the document itself, the document is not sufficient for a compliance file, whatever it says on the first page.
What this site can and cannot give you
Certificates are quoted here only where the document is on file and the model appears in it. At present that means Molicel models, whose data sheets and UN38.3, IEC 62133 and UL documents are archived and indexed. For Samsung SDI, LG Energy Solution and Panasonic we hold no certificate documents, and the pages say so rather than implying otherwise.
Where to go next
The individual standards are covered one page each in the compliance section, with what each one addresses, what document the buyer receives, and what it does not cover. If you need the documents for a specific consignment, the data sheet library lists every PDF held on file with the model it applies to.
Questions this guide does not answer in passing
Is UN38.3 the same as IEC 62133?
No. UN38.3 is a transport test series; IEC 62133-2 is a product safety standard. Passing one says nothing about the other, and a product going to market usually needs both the transport documents and the safety assessment.
Do I need a new UN38.3 summary if I change the pack?
The cell-level summary travels with the cell design. A new pack assembly is a different construction and is assessed separately, so the pack may need its own documentation depending on the configuration and the mode of transport.
What state of charge should cells ship at?
Partial charge, not full. Air transport of standalone lithium-ion cells is limited in state of charge, and full charge is worse for the cell during storage regardless of transport rules.
Can a distributor issue a certificate?
No. Certificates are issued to the manufacturer or the entity holding the approval. A distributor can pass on the manufacturer document, but it cannot be the certificate holder for someone else's design.
Is a UL file number valid for every model from that manufacturer?
No. A UL file covers the constructions listed in it. A model added later is only covered once the file is updated, and the earlier document does not imply coverage.
What documentation travels with an order?
UN38.3 test summary and the safety data sheet, matched to the actual shipping configuration. Certificates are quoted only where we hold the document and the model appears in its coverage list — that currently covers Molicel models, and no certificate documents are held for the other three brands.
Does a certificate cover every model from that manufacturer?
No. A UL recognition is issued under a file number that lists the constructions covered, and a model added later is only covered once the file is updated. The check is whether your model designation appears in that list, not whether the manufacturer holds a certificate at all.
Can cells ship by air?
Yes, under the applicable packing instruction and with the state of charge limited for standalone cells. The final word rests with the airline and the freight forwarder, and the configuration — cells alone, packed with equipment, or contained in equipment — decides which entry applies.
More guides
Keep reading
Want a second opinion on a shortlist?
Send the candidates you are weighing up. We will tell you which ones we can supply with documentation and which we cannot.