As you may know, the U.S. Department of Transportation has declared that, effective the first of this year, carrying spare lithium ion batteries in checked airline baggage is now against federal regulations. This affects mainly laptops and digital cameras. The batteries are fine if they are in the devices themselves, but cannot be transported outside the device unless it is in carry-on luggage in a clear plastic bag. The reason given for this is that supposedly these batteries create a fire hazard, and that loose batteries may have been responsible for some airplane fires in the past (including one in the cargo hold of a UPS plane bound for Philadelphia in February of 2006). According to the web site for the Pipeline and Hazardous Materials Safety Administration,
“Common consumer electronics such as digital cameras, cell phones, and most notebook computers are still allowed in carry-on and checked luggage. Moreover, any number of spare batteries for these devices will be allowed in carry-on baggage if they are properly protected from short circuiting and do not exceed 8 grams (~100 watt hours) of equivalent lithium content. Most lithium-ion cell phone and standard notebook computer batteries are below 8 grams (~100 watt hours) of equivalent lithium content. Batteries not installed in electronic devices are not permitted in checked baggage.”
Emphasis added. Calculating watt-hours is not something we lawyers like to do in our spare time (that’s for the engineers). The Department of Transportation states that many lithium ion batteries have noted on them their watt-hour rating. If it does not, “the watt-hour rating can be calculated by multiplying the battery voltage by the Ampere hour (Ah) or Milliampere-hour rating. These values are marked on most batteries.” This is not that onerous a task, but it is something we need to be aware of, so we can keep our spare batteries in the baggie next to our shampoo and deodorant.