If you're importing or exporting lithium batteries, one thing has changed for 2026 and it's easy to miss: the 30% state-of-charge (SoC) limit is no longer a recommendation — it's now a hard requirement for shipping standalone lithium-ion cells and batteries by air. Get this wrong and your shipment gets rejected at the terminal. This guide walks through the documents and numbers that keep a battery shipment moving.
1. The Document That's Non-Negotiable: UN38.3 Test Summary
You cannot legally ship a lithium battery without a valid UN38.3 test summary. It proves the battery passed a set of transport-safety tests. Two things to check carefully:
- It must match the exact battery model, capacity and configuration you're shipping — a summary for a 3,000mAh pack doesn't cover the 5,000mAh version.
- Carriers and customs cross-check the test summary against your commercial documents, so a mismatch means delays.
2. The 30% State-of-Charge Rule (Now Mandatory)
Starting January 2026, the 30% max charge is a strict legal requirement, not a guideline:
| What's shipping | UN number | Requirement |
|---|---|---|
| Standalone lithium-ion cells/batteries | UN3480 (PI965) | 30% max SoC |
| Batteries packed with equipment | UN3481 (PI966) | 30% max SoC (over 2.7Wh) |
| EVs / battery-powered vehicles | UN3556 (PI952) | 30% max SoC (over 100Wh) |
If a battery ships above 30% charge, an airline can refuse it outright. This is why manufacturers now discharge packs to a storage state before export — and it's a legitimate question to ask your supplier: "do you ship at ≤30% SoC and provide the UN38.3 summary?"
3. The Other Certifications Buyers Actually Ask For
- MSDS / SDS — material safety data sheet for chemical composition and handling. Carriers and customs ask for it routinely.
- CE — required for the European market.
- ISO9001 — quality management system, increasingly expected by B2B buyers.
- Target-market certs — UL for North America, and others depending on destination. A good supplier helps you get these for your market.
4. Air vs. Sea: The Rules Differ
Air has the strictest limits (the 30% SoC rule, specific UN numbers, UN38.3 mandatory). Sea follows the IMDG code — also requires UN38.3 and proper packaging, but the SoC rules are generally more flexible. For large energy-storage systems, sea freight is almost always the practical route, and the dangerous-goods declaration becomes critical.
5. A Checklist for Every Import/Export Order
- ☐ UN38.3 test summary matching the exact model you're shipping
- ☐ Correct UN number (3480/3481/3556…) on documents and packaging
- ☐ Discharged to ≤30% SoC (for air and when required)
- ☐ MSDS/SDS included with the shipment
- ☐ CE / target-market certifications in place
- ☐ Dangerous-goods declaration for sea freight
- ☐ Packaging that meets the carrier's marking and labeling rules
Rule of thumb for buyers: any serious lithium-battery supplier should be able to hand you the UN38.3 summary, confirm 30% SoC shipping, and explain the certification path for your country. If they can't, that's a red flag — not a detail to wave off.
Shipping lithium batteries doesn't have to be scary, but it is unforgiving about paperwork. Nail the UN38.3 summary and the 30% rule, and you've already avoided the two most common reasons shipments get stuck.
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