Solar installers in Florida are moving more battery-backed systems than ever. Home storage units, commercial battery cabinets and replacement modules are heavy, high-energy products, and carriers treat them with caution. If you sell, install or export them, the classification work has to be done before the product leaves the warehouse.
Why large lithium batteries are different
Small consumer cells have well-known packaging pathways. Large-format batteries and complete storage systems exceed many of those pathways in mass, watt-hours and fire risk. They are generally Class 9 miscellaneous dangerous goods, and the correct UN number depends on whether the batteries are shipped alone, packed with equipment or installed in the equipment.
Common UN numbers
- UN3480 lithium ion batteries, shipped alone.
- UN3481 lithium ion batteries contained in or packed with equipment.
- UN3090 / UN3091 for lithium metal batteries, shipped alone or with equipment.
- UN3536 lithium batteries installed in a cargo transport unit, used for battery systems built into containers or similar units.
- UN3171 for battery-powered vehicles and equipment in some cases.
Choose the entry that matches how the product is actually presented. See our overview of Class 9 shipping.
Test and design requirements
Lithium batteries must pass the UN Manual of Tests and Criteria, Section 38.3, and manufacturers need a test summary available on request. Large batteries over a certain mass often have specific packaging allowances in 49 CFR 173.185, and some products need approvals or special permits. Always review special permits if your product falls outside the standard provisions.
State of charge and condition
Air rules limit the state of charge for batteries shipped alone, and cargo-aircraft-only labels apply to many lithium battery shipments. Damaged, defective or recalled batteries require far stricter handling, and some carriers refuse them. Inspect every unit and keep records.
Packaging for heavy modules
Use strong outer packaging or a robust crate, immobilize the battery to prevent shifting and protect terminals against short circuits. Add thermal-event considerations such as non-conductive separators. Pallets should be strapped and wrapped, with corner protection and a clear orientation.
Modes and routes
Ground transport is the usual choice domestically. Ocean exports through Port of Miami or Port Everglades need vessel line acceptance and IMDG documentation; read about lithium batteries on ocean freight. Air shipments of large lithium batteries are often cargo-aircraft-only and tightly limited, and our lithium battery air checklist is a good place to start.
Storage before shipping
Warehousing large lithium batteries raises fire code and insurance questions. Talk to your insurer and local fire marshal, and consider specialized hazmat warehousing when volumes grow. For deliveries to installation sites, plan access and unloading equipment in advance.
Get help classifying
Because a wrong UN number can lead to rejection or liability, many manufacturers ask for a classification review. Start with a hazmat compliance consult or request a quote with your product specs.
Frequently asked questions
Are home battery systems hazmat?
Yes, lithium-based systems are typically Class 9 dangerous goods, with the UN number depending on packaging and whether the battery is installed in equipment.
Do I need UN 38.3 test results?
Yes. Manufacturers must have a test summary, and carriers or customs may ask for it.
Can I ship damaged batteries?
Damaged or defective lithium batteries have special requirements and are often refused. Contact a hazmat specialist before moving them.