Understanding Lithium Battery Classifications
Lithium batteries are regulated as Class 9 Miscellaneous Hazardous Materials. To properly package and label a shipment, you must first determine two things: the chemistry of the battery and how it is packed.
Lithium-ion batteries (rechargeable, used in laptops and phones) are classified separately from Lithium-metal batteries (non-rechargeable, used in watches and medical devices).
UN Numbers: Standalone vs. Packed in Equipment
The regulations assign specific UN numbers based on packaging configurations.
UN3480 designates Lithium-ion batteries shipped by themselves (standalone). UN3481 covers Lithium-ion batteries packed with equipment or contained within equipment. UN3090 and UN3091 are the equivalent numbers for Lithium-metal batteries.
How to Calculate Watt-Hours (Wh)
For lithium-ion batteries, regulatory thresholds are based on Watt-hours (Wh). If the Wh rating is not printed on the battery label, you must calculate it.
The Formula: Volts (V) x Amp-hours (Ah) = Watt-hours (Wh). Note: If the capacity is listed in milliamp-hours (mAh), divide by 1,000 to get Ah first.
Example: A power tool battery is rated at 18 Volts and 5,000 mAh. First, convert mAh to Ah: 5,000 / 1,000 = 5 Ah. Then calculate Wh: 18V x 5Ah = 90 Watt-hours.
Excepted vs. Fully Regulated Shipments
Small batteries (<= 100 Wh for packs, <= 20 Wh for cells) often qualify for 'excepted' status (Section II of IATA regulations). These shipments require the Lithium Battery Mark but do not require full Class 9 hazard labels or UN specification packaging.
Batteries exceeding these thresholds are fully regulated. They require Class 9 hazard labels, specific UN-tested packaging, dangerous goods declarations, and specialized hazmat training for the shipper.
Frequently asked questions
What is the State of Charge (SOC) limit for air transport?
IATA regulations mandate that standalone lithium-ion batteries (UN3480) shipped by air must be offered for transport at a State of Charge not exceeding 30% of their rated capacity.
Do I need a UN specification box to ship a laptop?
No, if the battery is contained within the laptop (UN3481) and falls under the 100 Wh limit, it generally only requires strong outer packaging that prevents accidental activation, not UN spec packaging.
Can I ship damaged or recalled lithium batteries by air?
No. Damaged, defective, or recalled (DDR) lithium batteries are strictly prohibited from air transport. They must be shipped via ground following specific DOT special provisions.
What information goes on the Lithium Battery Mark?
The mark must display the appropriate UN number(s) (e.g., UN3481) and a telephone number for additional information about the shipment.