Non-rechargeable and rechargeable lithium batteries, cell phone batteries, laptop batteries
Spare (uninstalled) lithium and lithium ion batteries must be carried in carry-on baggage only.
This covers spare lithium metal and spare rechargeable lithium ion batteries for personal electronics such as cameras, cell phones, laptop computers, tablets, watches, calculators, etc.
Size limits: Lithium metal (non-rechargeable) batteries are limited to 2 grams of lithium per battery. Lithium ion (rechargeable) batteries can contain up to 8 grams of equivalent lithium content per battery (up to a rating of 100 watt hours). These limits allow for nearly all types of lithium batteries used by the average person in their electronic devices. Passengers may also carry up to two larger lithium ion batteries that have from 8 to 25 grams of equivalent lithium content (about 100-300 watt hours). This size covers the larger after-market extended-life laptop computer batteries and some larger batteries used in professional audio/visual equipment.
Quantity limits: None for most batteries. There is a limit of two per person for the larger lithium ion batteries described above (8-25 grams/100-300 watt hours).
Batteries must be protected from damage.
Battery terminals (usually the ends) must be protected from short circuit (i.e., the terminals must not come in contact with other metal). Methods include: leaving the batteries in their retail packaging, covering battery terminals with tape, using a battery case, using a battery sleeve in a camera bag, or putting them snugly in a plastic bag or protective pouch.
See the regulation: 49 CFR 175.10(a)(18)
Tip: Newer lithium ion batteries have the watt hour (Wh) rating marked on them. To calculate watt hours, multiply the battery voltage by the Amp hours (Ah). To learn more about lithium batteries, their restrictions, and how to tell what size they are, go to http://SafeTravel.dot.gov
View our illustrated guide on Airline Passengers and Batteries.