BU-704a: Shipping Lithium-based Batteries by Air

Lithium batteries are dangerous goods and transporting them is only permitted with UN 38.3 certification according to the UN Manual of Tests and Criteria. The International Air Transport Association (IATA) assists by publishing the IATA Dangerous Goods Regulations (DGR) that helps classify, mark, pack, label and document dangerous shipments. DGR is recognized by all major airlines.

The lithium content in the battery governs the energy storage capacity (runtime) measured in watt-hours (Wh). The Wh measurement is used to limit the quantity a passenger can bring onboard an aircraft, what can be transported outside of the Class 9 dangerous goods designation, and what mandates Class 9.

To calculate the lithium content, multiply the rated capacity (Ah) times 0.3. For example, a 1Ah cell has 0.3 grams of lithium. To derive Wh, multiply Ah by the cell voltage of 3.6V. A typical laptop battery of 14.4V and 5Ah has 72Wh. (Lithium content: 5Ah x 0.3g = 1.5g x 4 cells in series = 6g).

IATA differentiates between batteries contained in the equipment (non-removable) and batteries that are packaged separately. If contained, such as in watches, smartphones or laptops, the Wh limit is ignored if less than 100Wh. However, if the battery is packaged with the equipment and is interchangeable, such as a removable pack of a power tools, then the battery must be counted. Figures 1a and 1b illustrate examples of “contained in equipment” and “packaged with equipment.”

Since 2016, lithium batteries can no longer be carried in passenger aircraft as cargo. Under DGR, the packaging instructions (PI) are organized into PI 965 to PI 970. PI 965 covers Li-ion cells and battery packs only (UN3480), while PI 966 includes Li-ion installed in equipment and PI 967 combines Li-ion with equipment (UN3481). Because of higher lithium content, lithium-metal batteries are handled separately under PI 968 to 970 (UN3090 and UN3092). Most lithium-metal are non-rechargeable.

Transporting lithium batteries is divided into two categories:

1. Non-Class 9 hazardous material shipment. It involves small batteries in limited quantities. Shipping restrictions also apply for courier and mail deliveries. Attach CAUTION labeling.

2. Class 9 hazardous material. This enables shipment of larger battery sizes and higher volumes.

Packaging Instruction 965 — includes loose Li-ion cells and battery packs (UN 3480)

Table 2 divides the transport of Li-ion products into four groups:

• Carry-on defines the quantity of Li-ion cells and battery packs a passenger can take on an aircraft;

• Section II specifies shipment of small Li-ion products in low numbers;

• Section 1B advises on the shipment of small Li-ion products in larger numbers;

• Section 1A governs larger Li-ion products;

Only Carry-on and Section II are exempt from Class 9 hazardous material designation. IATA mandates that cells and battery packs cannot be combined in the same shipping box. Use separate boxes.

Labeling

All Li-ion shipment must include the CAUTION labels as shown in Figure 3a to indicate the presence of lithium batteries. Since lithium batteries are only allowed in cargo aircraft, also attach the “Cargo Aircraft Only” label illustrated in Figure 3b. Batteries shipped Class 9 in Section IA and IB must include the Class 9 label as per Figure 3c. The package must also accompany shipping documents with name and address of consignor, date, phone number and description of shipment, including the UN number and weight.

30% State-of-charge Mandate

All lithium batteries shipped under PI 965 in Sections II, IA and IB must have a state-of-charge (SoC) of 30 percent. This mandate is added because Li-ion is more stable at low SoC than when fully charged. (An analogy is a boiler that is safer at low pressure than when the gauge touches the red line.) An open circuit voltage of 3.70V when rested indicates that the Li-ion cell is roughly at a 30 percent SoC. Discharge Li-ion to 3.65V/cell at moderate current. The 50mV overshoot compensates for the rubber band effect as the battery recovers to 3.70V/cell in time. (See BU-702: How to Store Batteries). Modern battery chargers and analyzers include the AirShip program.

Note:

• Li-ion voltages vary according to chemistry

• The SoC limit does not apply to Li-ion batteries that are packed with or installed in products.

General Transport Requirements

Packaging Instructions 966 and 967 (UN 3481)

PI 966 governs Li-ion cells and battery packs with equipment under UN 3481, and PI 967 oversees Li-ion cells and battery packs in equipment under UN3481 (Table 5). These rules are similar to PI 965 with the exception that Li-ion cells and battery packs can be shipped with, or in the equipment. Equipment means an apparatus requiring Li-ion products to operate.

Packaging Instruction 968 — permits lithium-metal cells and battery packs (UN3090)

Lithium-metal batteries have tighter shipping requirements than lithium ion batteries. Most Li-metal is non-rechargeable, and it is used in watches, medical instruments, pacemakers, sensors, memory retention, etc. There are also consumer-grade lithium-metal in AAA, AA, 9V and other formats. Table 6 lists the restrictions in the shipment of these batteries.

Packaging Instruction 969 and 970 (UN 3091)

PI 969 includes lithium-metal with the equipment under UN 3091, while PI 970 rules include lithium-metal in the equipment, also under UN 3091 (Table 7).

Shipping Prototype Batteries

Shipping prototype batteries, including annual production runs of no more than 100 cells, or batteries for testing, are exempt when adhering to shipping regulations CFR 49 173.185 (e). Shipping non-UN tested batteries is described in: 49 CFR § 173.185 - Lithium cells and batteries.

It is FORBIDDEN to ship damaged, defective, recalled or recycled lithium batteries by aircraft. This ban applies for loose cells or batteries, and those contained in equipment.