Six Facts to Establish Before Reading a Quantity Limit

Do not begin with a kilogram value copied from another shipment. Begin with these six facts:

1. Chemistry: lithium ion, including lithium-ion polymer, or lithium metal, including lithium alloy.
2. Configuration: batteries shipped alone, packed with the equipment they power, or contained in that equipment.
3. Rating or content: Watt-hours for lithium-ion cells and batteries, or lithium content for lithium-metal cells and aggregate lithium content for lithium-metal batteries.
4. Count: cells or batteries per item and per package, plus the number of equipment units where relevant.
5. Net battery weight: the combined weight of the regulated cells or batteries in each package.
6. Aircraft pathway: passenger aircraft or cargo aircraft only.

Condition, state of charge, UN 38.3 status, packaging, marks, labels, documents, origin, destination and operator variations remain additional checks. A complete set of quantity figures cannot make an otherwise ineligible shipment acceptable.

Why “How Many Batteries?” Has More Than One Answer

A shipper asking “How many batteries can I put in this carton?” may actually be asking several different questions:

• Is each lithium-ion cell at or below 20 Wh, or is each battery at or below 100 Wh?
• Is each lithium-metal cell at or below 1 g lithium content, or is each battery at or below 2 g aggregate lithium content?
• What is the maximum net battery quantity in one package for the applicable section and aircraft type?
• If batteries are packed with equipment, how many operating batteries and spare sets are allowed?
• If batteries are contained in equipment, does the four-cell/two-battery marking exception apply?
• How many packages are in the consignment?
• Are several compliant packages being combined in an overpack?

The first two questions help identify the size branch. The third concerns net kilograms per package. The fourth concerns the relationship between the battery count and the equipment. The fifth concerns limited hazard-communication relief. The sixth may affect whether that relief remains available. The seventh concerns a handling enclosure around packages that must already comply individually.

This is why neither 5 kg, 10 kg, 35 kg, four cells nor two batteries is a complete answer by itself.

What “Net Quantity per Package” Means

The IATA 2026 guidance defines net quantity as the weight or volume of the dangerous goods in a package, excluding the packaging material. For articles packed with or contained in equipment, the relevant net quantity is the net weight of the regulated article—in this case, the lithium cells or batteries—not the equipment and not the complete carton.

Keep these values separate:

A simple net-quantity example

Assume one package contains three battery packs, each with a verified physical weight of 1.6 kg:

3 batteries × 1.6 kg = 4.8 kg net battery quantity in the package

The 4.8 kg calculation says only how much regulated battery article is in that package. It does not establish whether the batteries are lithium ion or lithium metal, whether they are shipped alone or with equipment, which packing section applies, whether the flight can use passenger aircraft, or whether the package is acceptable.

Record the gross carton weight separately. If the batteries, equipment and packaging together weigh 18 kg, the package may have a gross weight of 18 kg while its net battery quantity remains 4.8 kg.

2026 Lithium-Ion Air Quantity Matrix

The public IATA flowchart separates lithium-ion cargo by configuration and rating. For lithium-ion cells, the size boundary shown is 20 Wh; for lithium-ion batteries, it is 100 Wh. The following table reproduces only the public orientation values needed to understand the quantity decision. It is not the complete packing instruction.

Source: IATA Guidance Document for Lithium Batteries and Sodium Ion Batteries — 2026, lithium-ion classification flowchart.

The words at or below and over matter. A 100 Wh lithium-ion battery belongs on a different size branch from a battery over 100 Wh, but that boundary does not determine the entire shipment. Use the dedicated guide to calculate and verify lithium battery Watt-hours before relying on a Wh value.

The matrix also does not show every requirement. UN 38.3 status, state of charge, packaging construction, marks, labels, documents, State and operator variations, approvals and route availability still need current review. In particular, the cited baseline guidance shows UN3480 batteries shipped alone as forbidden on passenger aircraft. A cargo-aircraft-only value must not be copied into a passenger-aircraft plan.

2026 Lithium-Metal Air Quantity Matrix

Lithium-metal cargo uses lithium content rather than Watt-hours to identify the small-content and larger-content branches. The public flowchart separates cells at 1 g lithium content and batteries at 2 g aggregate lithium content.

Source: IATA Guidance Document for Lithium Batteries and Sodium Ion Batteries — 2026, lithium-metal classification flowchart.

Do not calculate grams of lithium from voltage, Ah, mAh, Wh, runtime or total cell weight. Obtain the per-cell value from manufacturer-supplied, model-specific records and use the separate guide to verify lithium content and aggregate lithium content.

The cited baseline guidance shows UN3090 lithium-metal batteries shipped alone as forbidden as cargo on passenger aircraft. It also describes limited approval or exemption pathways. Those pathways are decisions for the responsible authorities, operator and appropriately qualified parties; they are not a workaround that can be selected from an online article.

Packed with Equipment: Count Operating Batteries and Spare Sets

For batteries packed with equipment under PI 966 or PI 969, the package must contain equipment that the batteries are intended to power. A charger, cable or adapter by itself is not the powered equipment and does not turn otherwise standalone batteries into packed with equipment.

The IATA 2026 packaging FAQ explains that the maximum number of batteries in a package is tied to the minimum number required to power the equipment, plus two spare sets. One set means the number of cells or batteries needed to power each piece of equipment.

This is a count test and a weight test at the same time. A permitted count does not override the applicable net-quantity limit.

Example: four tools and two spare sets

Assume four tools are packed in one outer package. Each tool requires one removable battery to operate, and all batteries are packed with—not installed in—the tools.

• Operating set: 4 batteries
• First spare set: 4 batteries
• Second spare set: 4 batteries
• Total count: 12 batteries

The public IATA FAQ uses this relationship to explain the two-spare-set rule. The shipper must still calculate the combined net battery weight, verify the Wh or lithium-content branch, apply the current packing instruction and satisfy the selected aircraft limit. If the 12 batteries exceed the applicable net quantity, the count relationship does not save the package.

Power banks need special attention. IATA treats a power bank designed primarily to charge another device as a battery, not as a battery contained in equipment. Putting a power bank beside a phone does not automatically make the power bank a spare battery packed with that phone under PI 966.

The Four-Cell/Two-Battery Rule Is a Marking Exception

The phrase “four cells or two batteries” is often repeated without its conditions. Under the cited 2026 IATA guidance, it concerns a limited battery-mark exception for specified Section II shipments in which batteries are contained in equipment.

The complete working question is whether:

• the shipment is prepared under the applicable Section II contained-in-equipment provision;
• each package contains no more than four cells or two batteries installed in equipment; and
• the consignment contains no more than two such packages.

When those conditions are met, the battery mark and the associated air waybill compliance statement may not be required under the cited provision. This does not mean:

• a package may contain only four cells or two batteries in every situation;
• four cells or two batteries are always exempt from dangerous-goods rules;
• net quantity per package no longer applies;
• UN 38.3, short-circuit protection, activation protection or package requirements can be ignored; or
• an airline must accept the shipment.

The IATA 2026 documentation FAQ also explains that a transport package may contain multiple retail boxes. If the package falls outside the small-consignment marking exception, the correct response is not necessarily to remove products; it may be to apply the required hazard communication and documentation while keeping within the applicable 5 kg net battery limit and all other Section II conditions.

Do not split one consignment across several air waybills to make the package count appear smaller. The same IATA FAQ expressly warns shippers and freight forwarders against splitting a consignment to avoid the marking condition.

IATA announced in September 2026 that its 2027 Battery Shipping Regulations include clarification on exclusions from the four-cell/two-battery limit. That announcement is a version-control warning, not permission to apply an unspecified future rule early. Use the edition effective when the shipment is offered and recheck the wording before publication or booking.

Package, Consignment and Overpack Are Different Levels

Quantity mistakes often begin when data from one physical level is placed in a field belonging to another.

Do package limits apply to the total overpack weight?

The IATA 2026 overpack FAQ says that packing-instruction quantity limits refer to the maximum net weight of cells or batteries in each package. It does not specify a separate aggregate lithium-battery quantity limit for the overpack, provided every package remains within its applicable limit.

That answer does not make an overpack unrestricted. Each package inside it must already be properly prepared and in suitable condition. Required package marks and labels must remain visible or be reproduced on the overpack as applicable. The overpack must be identified, its packages must be secured, and applicable segregation and compatibility rules still matter. Operator variations may also be more restrictive.

Example: three packages in one overpack

Assume three packages each contain a verified 4.0 kg net quantity of batteries and each package is within its applicable 5 kg limit. Placing those packages in one overpack does not change each package's net quantity to 12 kg. The package-level values remain 4.0 kg, 4.0 kg and 4.0 kg.

This example does not prove that the overpack is acceptable. The configuration, packing section, marks, labels, documentation, segregation, overpack construction and operator requirements must still be reviewed. If one package contains 5.4 kg under a branch limited to 5 kg, an overpack cannot cure that package-level failure.

Passenger Aircraft and Cargo Aircraft Only Are Separate Decisions

The same configuration can have different values for passenger aircraft and cargo aircraft only. Read the aircraft column before reading the number.

Under the cited 2026 baseline guidance:

• UN3480 lithium-ion batteries shipped alone under PI 965 are forbidden as cargo on passenger aircraft;
• UN3090 lithium-metal batteries shipped alone under PI 968 are forbidden as cargo on passenger aircraft; and
• qualifying packed-with-equipment and contained-in-equipment branches show passenger-aircraft limits of 5 kg net quantity per package, while some larger branches show a higher 35 kg cargo-aircraft-only limit.

CAO = 35 kg does not mean that any battery package up to 35 kg can fly. It means that the public flowchart shows a maximum net quantity of 35 kg per package on the cargo-aircraft-only branch for the stated configuration and section. The cargo still needs the correct packaging, hazard communication, documents, state of charge where applicable, current variations and operator acceptance.

An operator may decline a shipment even when the package appears to fall below a published baseline maximum. The operator's aircraft, facilities, route, risk controls and internal approvals can produce a stricter operational result. The IATA Battery Shipping Regulations covers variations and acceptance as parts of the complete current process.

Worked Package-Quantity Examples

These fictional examples demonstrate how to organize information. They do not classify a shipment or replace the current packing instructions.

Example 1: small lithium-ion batteries shipped alone

A package contains eight lithium-ion battery packs. Each battery is 80 Wh and weighs 1.2 kg.

• Battery count: 8
• Individual battery weight: 1.2 kg
• Net battery quantity: 8 × 1.2 kg = 9.6 kg
• Candidate public branch: UN3480 / PI 965 / Section IB, because each battery is at or below 100 Wh
• Passenger aircraft: forbidden under the cited baseline branch
• Public CAO net-quantity limit: 10 kg per package

The arithmetic places the package below the public 10 kg value, but it is not an acceptance decision. The exact model, UN 38.3 status, state of charge, package tests, marks, labels, declaration, current variations and operator acceptance still need review.

Example 2: batteries packed with power tools

Four power tools and 12 removable batteries are packed together. Four batteries make one operating set, and eight batteries make two spare sets.

• Equipment units: 4
• Batteries needed to power all equipment: 4
• Two spare sets: 8
• Total batteries: 12
• Individual battery weight: assumed 0.35 kg
• Net battery quantity: 12 × 0.35 kg = 4.2 kg

The equipment relationship and 4.2 kg net quantity both need to be checked against the actual Wh rating, current PI 966 section and aircraft pathway. The count alone does not identify Section I or Section II, and the weight alone does not prove that the batteries are genuinely packed with equipment they are designed to power.

Example 3: batteries contained in equipment

A consignment contains two transport packages. Each package contains two pieces of equipment, and each piece contains one qualifying small battery.

• Installed batteries per package: 2
• Packages in the consignment: 2
• Candidate question: whether the cited Section II four-cell/two-battery marking exception applies

The example may meet the count and package-number elements of that narrow exception, but the responsible party must still confirm the correct Section II pathway and every other condition. The exception concerns hazard communication; it does not make the batteries unregulated or the packages automatically acceptable.

Example 4: several packages in an overpack

Three individually prepared packages are secured in one overpack. Each package has a net battery quantity of 4.0 kg under a branch whose limit is 5 kg.

• Package-level values: 4.0 kg each
• Combined arithmetic inside the overpack: 12.0 kg
• Compliance question: each package must remain within its own limit; overpack marking, visibility, segregation and operator conditions are separate

Do not enter 12.0 kg as though it were the net quantity of one package. Do not use the absence of a public overpack aggregate limit to ignore package defects or other overpack requirements.

Common Lithium Battery Quantity-Limit Errors

Using gross carton weight as net battery quantity

Gross weight includes packaging and may include equipment or accessories. Net quantity for the battery entry is the weight of the regulated cells or batteries in the package.

Treating Wh as kilograms

Wh is an energy rating. It helps identify the lithium-ion size branch; it is not a physical weight.

Using one battery's weight as the package total

Multiply the verified individual weight by the number of identical batteries in that package. For mixed models, calculate and add each model subtotal.

Mixing lithium-ion and lithium-metal thresholds

Lithium ion uses Wh for the cited size branch. Lithium metal uses lithium content per cell and aggregate lithium content per battery. Do not apply 20 Wh/100 Wh to lithium metal or 1 g/2 g to lithium ion.

Selecting a section from the UN number alone

One UN entry can lead to different sections. Configuration, rating/content, test status and other conditions must be established before the relevant branch can be confirmed.

Calling four cells or two batteries a universal limit

The cited rule is a limited marking exception for specified contained-in-equipment Section II consignments. It is not the general maximum number of batteries in a package.

Ignoring the two-package condition

For the cited small-consignment marking relief, the number of packages in the consignment matters as well as the number of installed cells or batteries per package.

Treating an overpack as a way around a package limit

An overpack combines packages for handling. It does not authorize an inner package that exceeds its own applicable net-quantity limit.

Using a CAO value for passenger aircraft

The aircraft columns are different. Standalone UN3480 and UN3090 are shown as forbidden on passenger aircraft under the cited baseline rules.

Assuming the regulatory maximum guarantees acceptance

State and operator variations, aircraft and facility capability, route, approvals and current booking policy can be stricter.

Reusing an old matrix after the effective edition changes

The ICAO Technical Instructions page states that the 2025–2026 edition remains valid through 31 December 2026. IATA has already released its 2027 manuals and identified battery-related revisions. Confirm the effective edition and current addenda whenever the shipment date or publication date changes.

What a Quantity Result Cannot Decide

Knowing the battery count and net battery kilograms does not determine:

• the final UN entry or packing-instruction section;
• whether the exact design type has passed the applicable UN 38.3 tests;
• the required state of charge;
• the correct inner and outer packaging or performance standard;
• required marks, labels or dangerous-goods documentation;
• whether the cargo is a prototype, low-production design, used battery, waste battery, damaged battery, safety-defective battery or recalled battery;
• whether a State approval or exemption is available;
• whether an operator variation prohibits or restricts the shipment;
• whether a particular airport, aircraft or route can handle it; or
• whether export, transit, customs or destination controls are satisfied.

Use the UN3480 vs UN3481 guide for lithium-ion configuration and the UN3090 vs UN3091 guide for lithium-metal configuration. For the separate reduced-charge question, use the lithium battery state-of-charge guide.

Physical preparation remains separate. Review the dedicated guidance on lithium battery packaging, marks and labels and the shipping documents checklist.

Pre-Enquiry Air Quantity Checklist

Before requesting an air-shipping option, confirm that:

1. the chemistry is identified as lithium ion or lithium metal;
2. the exact cell, battery and product models are recorded;
3. the physical configuration is documented as standalone, packed with equipment or contained in equipment;
4. Wh or lithium content comes from model-matched responsible information;
5. appropriately trained dangerous-goods personnel have identified the current packing branch;
6. cells and batteries are counted at item and package level;
7. the net weight of the regulated cells or batteries is calculated separately for every package;
8. equipment and packaging weight are excluded from that net quantity;
9. gross package weight, dimensions and package count are recorded separately;
10. the passenger-aircraft or cargo-aircraft-only pathway is explicit;
11. any equipment/spare-set relationship is supported by the actual products;
12. any four-cell/two-battery marking exception is checked together with the consignment package count;
13. any overpack arrangement is documented without replacing the package-level data;
14. condition, UN 38.3 status, state of charge, packaging, marks and documents are reviewed separately; and
15. current State/operator variations, approvals, route capability and acceptance remain open until confirmed.