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The U.S. DOT advises that any spare batteries should be stored in a zip-lock bag or the factory packaging to prevent short-circuits.  (Source: U.S. Department of Transportation)
New rules limit lithium content in batteries carried on aircraft

New rules went into effect today that could affect travelers who carry portable electronics on flights. The new regulations limit the amount of lithium in luggage and carry-on items -- specifically with regards to lithium in batteries.

The new rules state that spare batteries cannot be packed inside checked luggage, but spare batteries can be carried on board in carry-on baggage. Those brave enough to check baggage with electronic devices inside can leave installed batteries in the devices.

The U.S. Department of Transportation does not specify how many batteries are acceptable for travel.  The Department states passengers can carry spare batteries for electronic devices and that the lithium content in all batteries must weigh less than 25 grams.

To help explain the strange equivalent lithium content rule, Safetravel.dot.gov uses an example dividing the total amount of lithium as Watt-hours. The DOT claims lithium grams is roughly equivalent to 300 Watt-hours of battery time.

The popular Dell XPS m1330 notebook uses several different batteries. The 9-cell batteries, the largest available for the system, are rated at 85 Watt-hours. That would mean a pair of spare batteries for the notebook (170 Watt-hours) are well within the 25 gram (300 Watt-hours) total aggregate lithium content.   However, a passenger can only care the installed 9-cell battery with two spares before exceeding the 25g limit.

Devices that use lithium-metal batteries have a limit of two grams of lithium-metal per battery and according to Safetravel.dot.gov almost all lithium-metal batteries used in consumer devices comply with that limit. However, devices with lithium metal-batteries over the two gram limit are barred from the aircraft entirely.

These new rules are due to the potential fire hazard posed by rechargeable lithium batteries. The massive recalls and wide spread reports of fires resulting from laptop batteries resulting in the massive battery recalls of 2007 sparked the new battery policies now in effect.

However, the FAA is very clear on why such strict limits must be imposed.  In a statement released yesterday, the Administration stated, "Safety testing conducted by the FAA found that current aircraft cargo fire suppression system would not be capable of suppressing a fire if a shipment of non-rechargeable lithium batteries were ignited in flight."


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RE: Are we missing thr MUCH bigger story?
By Fritzr on 1/2/2008 3:44:09 AM , Rating: 2
Swissair Flight 800 blew up in flight. First reports caused major public uproar with speculation that the aircraft had been bombed or hit with an anti-aircraft missile. The final report was onboard fire that detonated the empty fuel tank in the aircraft midsection

A cargo plane went down in Florida due to an improperly packed load of gas cylinders. Final report indicates crew was likely dead from the fire before impact.

Every time a plane goes down and the reson is found to have been preventable there is a media uproar followed by FAA rules aimed at preventing it happening a second time. This time they noted a potential safety hazard that has an occurrence rate greater than what is allowed for aircraft crashes. To give an idea of perception, on one immigration forum an airline is currently blacklisted due to frequency of crashes being greater than 1 per decade worldwide.

The rules are often changed after accidents of this sort. The Flight 800 crash was due to causes that had already been identified and had previously been ruled allowable as long as future aircraft were not built with the same fault. The reasoning was that aircraft that had the fault had no record of accident due to the fault, so the risk was acceptable for the remaining life of the existing fleet. The fault was marginally flammable insulation. Difficult to ignite, self sustaining flame once lit, no fire suppression system where the fire burned to save weight.

The Florida crash was due to a shipper ignoring the rules for packing.

Lithium batteries can cause fires when used correctly. These fires are rare. Lithium batteries can cause fires when shorted. These fires are the reason for the label advising you that shorting a battery is a *very* bad idea. Will you bet your life that the passenger in the next seat packed the batteries correctly? The TSA & FAA obviously have decided that based on past history they can't trust 100% of all passengers 100% of the time to pack hazardous materials correctly.

It would be nice if TSA workers were properly trained, but that is an entirely different problem. Some of the 'weapons' seem silly, but next time you get a chance, contact a hospital that maintains a ward for the suicidally depressed and ask what their patients have used to kill themselves. Amazing what can be used when you put your mind to it and don't mind using things "incorrectly".


RE: Are we missing thr MUCH bigger story?
By Alexstarfire on 1/2/2008 4:13:18 AM , Rating: 2
Well, unless they packed the Li-Ion battery with a box full of metal, then yea, I would. I think the whole point is that they allow some Li-Ion batteries, but not all of them. If they outright banned them all then I could understand a little bit. But they are saying that you can have them if they are being used and not while they aren't, generally speaking. That doesn't make any sense. They are only going to explode when being used, ie charging or using the device it's in. I have yet to hear of one exploding because it was stored improperly or wasn't in use.


RE: Are we missing thr MUCH bigger story?
By PandaBear on 1/2/2008 11:49:27 AM , Rating: 2
Paper clip with knock off batteries that has no short protection?


By TomZ on 1/2/2008 12:20:57 PM , Rating: 2
That would be a more general hazard - it would threaten our safety in our offices, homes, in cars, trains, etc. - in other words it is inherently unsafe and should not be allowed generally, let alone on planes.


By Shining Arcanine on 1/2/2008 6:37:03 AM , Rating: 1
"Will you bet your life that the passenger in the next seat packed the batteries correctly?"

My life does not depend on whether the passenger in the next seat packed his batteries correctly, as there is neither correct nor incorrect way of packing them.


By TomZ on 1/2/2008 8:24:38 AM , Rating: 2
Nice post, however, it all hinges on some incorrect information:
quote:
Lithium batteries can cause fires when used correctly. These fires are rare. Lithium batteries can cause fires when shorted.

That is incorrect - these batteries will only cause a fire when they are defective. Under normal circumstances, it is impossible for them to catch fire during charge or discharge operations, including short-circuit. All these types of batteries have built-in protection against short-circuit as well as over-temperature that could lead to fire.

This is the reason why consumers can't buy these types of batteries (the raw batteries themselves) off-the-shelf - we can only buy ready-made "smart" battery packs. And when an engineer designs these types of batteries into a product, they work directly with the battery manufacturer to ensure that proper safety circuits are built-in.

Obviously, these safety measures are nullified when the battery itself is defective, but that is the exceptional case, not the normal case. And as I said before, if you look at the statistics (handful of fires compared to billions of batteries in use), the incidence of these fires is very very low.


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