Effective January 1, 2008, the Department of Transportation through the Pipeline and Hazardous Materials Safety Administration will no longer allow loose lithium batteries in checked luggage.
Spare batteries are the batteries you carry separately from the devices they power.
When batteries are installed in a device, they are not considered spare batteries.
You may not pack a spare lithium battery in your checked baggage.
You may pack spare lithium batteries in carry-on baggage.
Keep spare batteries in the original retail packaging, to prevent unintentional activation
or short-circuiting.
If original packaging is not available, effectively insulate battery terminals by isolating spare
batteries from contact with other batteries and metal. Place each battery in its own protective case,
plastic bag, or package. Do not permit a loose battery to come in contact with metal objects, such
as coins, keys, or jewelry.
For loose batteries, place tape across the battery's contacts to isolate terminals. Isolating terminals prevents short-circuiting.
There is generally no restriction on the number of spare batteries allowed in carry-on baggage. However,
you may carry no more than two larger batteries, in the range of 100-300 watt hour rating. See examples below.