Come 1 January 2014, new regulations relating to lithium batteries of the IATA (International Air Transport Association) will kick in. From that date onwards, some lithium batteries or combinations of batteries cannot be shipped as they will be considered as "dangerous goods". To avoid inconvenience (and disappointment), read the gadget's specifications carefully before purchasing it.
Generally, lithium-ion batteries with laptops, cameras, mobile phones, etc will be limited to a single battery (that's within the product), and one additional spare battery. Still, you might want to double-check the following, just in case.
Lithium-ion batteries with
Lithium metal batteries with
To calculate Wh:
mAh/1000 x V (volts),
where mAh = milliamps, and V = volts.
For a full list of regulations for lithium batteries, click here.