Lithium-ion batteries pretty much power everything
you use for your underwater photos and videos. Now
the Federal Aviation Administration (FAA) has handed
down new regulations for how you must carry them
when you fly.
Don't pack spare lithium-ion batteries in checked
baggage, as the FAA says they "present a risk of both
igniting and fueling fires in aircraft cargo/baggage compartments."
If they're found during a random search, the
batteries may be removed, leaving you in a pickle.
So you must carry them with you, but the FAA is
being stricter on how you pack them in your carry-on
luggage. It will provide "limited exceptions for passengers...
who carry on spare lithium batteries for personal
use." "Spare" refers to batteries not installed within a
portable electric device like a laptop or tablet. The definition
of "limited" is vague, but you may assume that
you'll be fine with two to three camera batteries and a handful of other lithium-ions. Spare batteries' terminals
must be "individually protected" to prevent short circuits,
and they must be packed so as not to be able to
come into contact with other metal objects.
The new rules also stipulate the Watt-hour capacity
of batteries you may carry. If you have lithium batteries
of 100Wh, you may carry up to three (two spares and
one in the device) in your carry-on. If your batteries are
over 100Wh but less than 160Wh, you must seek approval
from the air carrier to do so. Practically most SLR and
still-camera batteries fall well within this limit, but larger
video camera batteries may exceed it.
Although these guidelines are currently limited to
U.S.-based airlines and flights that depart or land at
U.S. airports, it is likely they'll extend to other countries
and airlines, too. So check with your airline at the time
of booking to ask what their current policy is. And to
be well informed before you get to the airport, read the
entire FAA document (https://www.faa.gov/other_visit/aviation_industry/airline_operators/airline_safety/safo/all_safos/media/2015/SAFO15010.pdf) so that airport
bag handlers don't ruin your next dive trip.