Battery enthusiasts who enjoy lining their checked baggage with excess power supplies are out of luck in 2008 under new government travel regulations, but it looks as though the average traveler with a laptop, cell phone or digital camera will not encounter nearly as much hassle as they might should they be holding more than 3 ounces of moisturizer.

Starting January 1, passengers will not be able to put loose, lithium-based batteries in their checked bags due to the possibility of fire, according to the Transportation Security Administration (TSA). Batteries that are attached to their designated devices, however, are permitted. Batteries rolling around with your clothes? Denied. Batteries installed in that extra digital camera? Good to go. Spare batteries must be packed with carry-on luggage.

TSA has imposed some restrictions based on lithium content for carry-on bags, but the 8 grams of allowable lithium basically covers most consumer electronics devices.

"All lithium ion batteries in cell phones are below 8 gram equivalent lithium content [and] nearly all laptop computers also are below this quantity threshold," according to the TSA.

The rules get a bit tricky when distinguishing between lithium-ion and lithium-metal batteries, however.

Most widely used consumer electronics use lithium-ion batteries, and the TSA will allow these batteries in checked and carry-on luggage provided they are installed in a particular device. Spare lithium-ion batteries will have to be packed in carry-on luggage. Passengers are allowed any lithium-ion batteries that contain less than eight grams of lithium, and are allowed two additional batteries that have up to 25 grams of lithium total.

Something that falls between that 8 and 25 gram threshold is this 130 watt-hour "universal" lithium-ion battery.

Lithium-metal batteries, meanwhile, which are apparently somewhat less stable than lithium-ion batteries, face tougher restrictions. They can be checked if they are installed a device, but travelers are only allowed lithium-metal batteries if they have less than 2 grams of lithium content. The average traveler, however, is probably not going to be holding many lithium-metal based batteries.

It appears that those who might run into the biggest problems are audio/visual professionals with a mountain of excess equipment. But those of us with our laptops, iPods, digital cameras and cell phones appear to be safe, provided they are attached to our devices or placed in carry-on luggage.

Why the concern? TSA said there is "no explosion hazard" with lithium batteries, but "the Federal Aviation Administration has studied fire hazards associated with both primary and lithium-ion cells."

Naturally, TSA would like to avoid battery fires altogether, but the idea is that should one occur, they would prefer it happen in the actual cabin so flight crews could try to put it out. If a battery catches fire in the luggage bay below the passengers, crews have no way of getting down there to extinguish it.

Check out the video above for some helpful tips on how a) not to react when your laptop explodes into flames at LAX ("Move away from the computer!") and b) how to extinguish a battery fire with the contents of the drink cart. Um, maybe you want to avoid using a hot plate (minute 2:00)?

No word, however, on whether TSA has been training its screeners on the art of lithium-ion vs. lithium-metal battery detection.