These definitions are provided for ease of use of the SafeTravel website.
Carry-on baggage. The baggage you carry with you on the plane and typically stow in the overhead bin or beneath the seat in front of you.
Checked baggage. The baggage you give to the airline for handling prior to boarding the plane.
Equivalent Lithium Content (ELC). ELC is a measure by which lithium ion batteries are classified. 8 grams of equivalent lithium content are equal to about 100 watt-hours. 25 grams of equivalent lithium content are equal to about 300 watt-hours.
You can arrive at the number of watt-hours your battery provides if you know how many milliamp hours and volts your battery provides:
mAh/1000 x V = wh
Most lithium ion batteries marketed to consumers are below 100 watt-hours (8 grams ELC). If you are unsure of the watt-hour rating of your lithium ion battery, contact the manufacturer.
Lithium Batteries. When you see this term alone on SafeTravel pages, it refers to both lithium ion batteries and lithium metal batteries. Lithium polymer batteries are a kind of lithium ion battery, and so are also included in this term.
Lithium Ion Batteries. These are rechargeable lithium batteries, like the ones found in cameras, cell phones, laptop computers, and radio-controlled toys. Lithium polymer batteries are a kind of lithium ion battery.
Larger Lithium Ion Batteries contain between 8 and 25 grams
Equivalent Lithium Content (ELC). Some very large after-market laptop computer batteries, and some batteries used for professional audio-visual application, fall within this definition.
Smaller Lithium Ion Batteries contain up to 8 grams
Equivalent Lithium Content. Cell phone batteries and most laptop computer batteries fall below the 8 gram threshold.
Lithium Ion Batteries with over 25 grams ELC are forbidden in air travel.
Lithium Metal Batteries. These are lithium batteries which can not be recharged. They are designed to be discarded once their initial charge is used up.
Larger Lithium Metal Batteries contain over two grams of lithium, and are
forbidden in air travel. (No common consumer lithium metal batteries are in the “larger” category.)
Spare Batteries. Spare batteries, also called “loose” batteries, are batteries which are not installed in equipment. A lithium ion battery inside your computer is an installed battery. A battery you carry separately in case that battery runs low is a spare battery.
Watt-hour. For the purposes of this page, the watt-hour serves as an indirect measure of
Equivalent Lithium Content (ELC). 8 grams ELC are about equal to 100 watt-hours.