The energy stored in batteries can cause a fire, if the batteries are not handled properly.
 

There have been a number of incidents on or near aircraft in which batteries and their products caused fires.  While recent news reports have highlighted the problems with Lithium batteries, there have been fires caused by other types as well.

The U.S. Department of Transportation has issued recommendations to passengers regarding safe traveling with battery operated products. Please check their website:  http://safetravel.dot.gov/index.html

There are also U.S. and International Transportation regulations concerning shipment of certain types of batteries and products with those batteries.

You need to take precautions when traveling with, or shipping, batteries or cordless products.

1. When traveling with OR SHIPPING a cordless tool, make sure that (a) the switch is in it’s locked off position (if the product has a lock-off), and/or (b) the switch is protected so that other contents in the box/bag cannot turn it on.
2. When traveling with or shipping a battery pack not in a tool/product, make sure the terminals are covered with insulation, and make sure that other contents in the box/bag will not defeat that insulation.  Most power tool batteries come with caps to cover the terminals.  If you do not have the cap, then tape over the terminals and put the battery in a plastic bag.  Keep the battery away from metals that could puncture the bag, including keys and the like.
3. When shipping any Lithium batteries, or products that contain Lithium batteries, significant additional precautions MUST be taken:

1. There are restrictions on the size and number of cells/batteries that can be shipped in a single package.
2. There are restrictions on the type of packaging that must be used and specifications for qualifying packaging when shipping lithium based battery/products.  Don’t just put a Lithium based battery/product in a cardboard box and ship it.
3. The battery and product must be packed so that it is protected from short circuiting and inadvertent turn-on.
4. In some cases, you need to declare to the shipper that the package contains Lithium-Ion (or Lithium-metal) batteries.
5. Depending on the contents, you might need to ship the product via ground, rather than air and/or mark the carton “not for shipment on passenger aircraft.”