New Lithium Battery Rules for U.S. Airplanes

Starting in 2008, there are new rules for bringing lithium batteries on airplanes:

The following quantity limits apply to both your spare and installed batteries. The limits are expressed in grams of "equivalent lithium content." 8 grams of equivalent lithium content is approximately 100 watt-hours. 25 grams is approximately 300 watt-hours:

  • Under the new rules, you can bring batteries with up to 8-gram equivalent lithium content. All lithium ion batteries in cell phones are below 8 gram equivalent lithium content. Nearly all laptop computers also are below this quantity threshold.

  • You can also bring up to two spare batteries with an aggregate equivalent lithium content of up to 25 grams, in addition to any batteries that fall below the 8-gram threshold. Examples of two types of lithium ion batteries with equivalent lithium content over 8 grams but below 25 are shown below.

  • For a lithium metal battery, whether installed in a device or carried as a spare, the limit on lithium content is 2 grams of lithium metal per battery.

  • Almost all consumer-type lithium metal batteries are below 2 grams of lithium metal. But if you are unsure, contact the manufacturer!

Near as I can tell, this affects pretty much no one except audio/visual professionals. And the TSA isn't saying whether this is a safety issue or a security issue. They aren't giving any reason. But those of you who paid close attention to the Second Movie-Plot Threat Contest know of the dangers:

Terrorists camouflages bombs as college textbooks, with detonators hidden in the lithium-ion batteries of various electronics. The terrorist nonchalantly wanders up by the cockpit with his armed textbook and detonates it right after the seat belt sign goes off, but while the plane is still over an inhabited area. Thousands die, with most of the casualties on the ground.

Chat about the ban on FlyerTalk. Does any other country have any similar restrictions?

EDITED TO ADD (12/28): It's not a TSA rule; it's an FAA rule.

The FAA has found that current systems for putting out aircraft cargo fires could not suppress a fire if a shipment of non-rechargeable batteries ignited during flight, the release said.

Here's the actual rule; it's the DOT that published it. Lithium batteries have been banned as cargo for a long time now. This is the DC-8 fire that led to the ban.

Posted on December 28, 2007 at 3:05 PM • 55 Comments


JosephDecember 28, 2007 3:19 PM

Best entry in the official FAQ:

"Q. What happens if my battery smokes or causes a fire during my flight?
A. Immediately alert the flight crew. Let the flight crew handled the incident. Members of the crew have access to fire extinguishers and are trained to handle such incidents."

If that unfortunate situation happened to you, how many lifetimes would you be on the no-fly or equivalent lists, because you were involved in an "incident" of some kind?

Toby StevensDecember 28, 2007 3:28 PM

Of course the average TSA worker will be quite capable of identifying the equivalent lithium content of the power source in any item. Just like any of the passengers.

ZDDecember 28, 2007 4:03 PM

Looks like a safety issue, not security. The rules about checked luggage are stricter than for carry-ons: presumably this is because a fire in the cabin will be noticed faster, and can be extinguished easily unlike a fire in the hold. They particularly target spare batteries in the hold, I imagine since spares are more likely to have their contacts exposed and potentially available to create a short.

The apparent arbitariness of the limits is typical of TSA's culture of rules, but other than that it's actually a pretty reasonable requirement.

nostromoDecember 28, 2007 4:17 PM

but you missed the weirdest part of the new rules, near the beginning of the article:

* Spare batteries are the batteries you carry separately from the devices they power. When batteries are installed in a device, they are not considered spare batteries.
* You may not pack a spare lithium battery in your checked baggage
* You may bring spare lithium batteries with you in carry-on baggage – see our spare battery tips and how-to sections to find out how to pack spare batteries safely!
* Even though we recommend carrying your devices with you in carry-on baggage as well, if you must bring one in checked baggage, you may check it with the batteries installed.

These rules would sound equally plausible if you inverted them, e.g. replaced "may not" by "may" and "may" by "may not". (They would almost continue to sound plausible if you did it randomly instead of consistently.)

An interesting strategy for the bold traveler would be to make a printout of the instructions
to show to security personnel in case of any dispute, but with "Forbidden" replaced by "Recommended" for everything in the last section that the traveler would like to do, and a random sprinkling of "Permitted" and "Recommended"s replaced by "Forbidden" to keep the number of Forbiddens the same.
Take a look at the Dept of Transportation web site, you will see what I mean:
- always assuming you can get to the end of it without your eyes glazing over ...

SmithyDecember 28, 2007 4:49 PM

Just thought I'd mention that the Dept of Transportation thinks that a cargo plane fire earlier this year was caused by lithium batteries.

From what I could tell, the DoT banned pallet-sized packages of multiple lithium batteries from flight on passenger airlines. This new ban is just the TSA attempting to prove it is paying attention to the DoT and the NTSB, and is therefore worth having the TSA exist.

Eh, right.... security theater.

Stephan SamuelDecember 28, 2007 5:06 PM

This appears to be only safety and not security, similar to compressed gas canisters. Unfortunately, airlines (and the TSA) seem to have rules that seem arbitrary in places. I'm allowed to check an inflatable life jacket -- every seat has one on some airplanes -- but commercial 12g CO2 cannisters are disallowed.

One way or another, whether you like it or not, flying is dangerous. Little changes can have large effects.

Toby Stevens is correct: there's going to be a big learning curve on the part of the TSA and travellers. There are also going to be a lot of annoyed business travellers who lose expensive spare laptop and phone batteries out of checked luggage.

rhDecember 28, 2007 5:47 PM

This is a fire safety issue. There have already been aircraft fires due to these batteries. It's very hard to fight a fire while in flight, and all of the rules are consistent with reducing fire risk. Even the separate battery is consistent with that. There is a much higher risk of fire due to accidental short circuit of exposed batteries than there is from batteries installed in equipment.

Of course TSA couldn't be bothered to explain any of this. That is just part of their mindless obedience culture.

LeoDecember 28, 2007 6:04 PM

If they're measuring it in "equivalent lithium content" how long will it be before someone's medication is confiscated?

Why can't they express the limitations in terms mere mortals and even TSA employees might be able to find on the battery label or at the very least calculate from what's on the battery label? Why the need to obfuscate?

Erik V. OlsonDecember 28, 2007 6:09 PM

1) This isn't a TSA rule, this is a FAA rule.

2) Why? The FAA was nervous about the random lithium battery catching fire in a notebook. Tests were done. Problem? The cargo hold fire extinguishers don't do anything to a Li-Ion battery fire.

Arguably, it's a bit of an overreaction, but I'll be honest -- I am more worried about a lithium battery catching fire in the cargo hold than I am about a hijacker taking over a plane. Not very worried, but I've seen those batteries burn, they don't mess around.

DBHDecember 28, 2007 6:27 PM

My laptop battery is 85 Whr, so we aren't far from the limit. I'm expecting the new rules will cause all sorts of problems...

In truth, there is an enormous amount of energy in a laptop battery, always thought that was a hole...

Scott KDecember 28, 2007 8:15 PM

So is the concern about fires with "non-rechargeable lithium batteries"--they make those?--or rechargeable? The releases seem to indicate concern over fires of the former, thus restrictions of the latter.

Erik V. OlsonDecember 28, 2007 8:36 PM

Scott K: Non-rechargeable (or "Primary") lithium batteries have been banned as cargo on airliners since 2000. This new restriction is on rechargeable (or "secondary") batteries.

As to "do they make those?", they're an incredibly common battery, because primary lithium cells have a notably higher voltage than other batteries. Any 3V coin battery you see is a primary lithium battery.

LorenDecember 28, 2007 9:30 PM

Alright. I'm bored. Half the time TSA freaks on our microphones, the rest of the time they need us to power up the hard disk recorder (when they aren't trying to drop it !) to prove its not a bomb.

Yes, I believe in security. And yes, I try to live within the [rules]. But this reg is so obfuscated ... so many boards and blogs are asking "wha's up," that neither normal folk nor TSA will know how to apply it. What an abortion.

I can't wait to get to the airport on Jan 2.

Scott KDecember 28, 2007 10:17 PM

Erik: Re: Non-rechargeable Li batteries: Oh yeah, those. :]


Re: Either type: What's the likelihood that any of them will spontaneously short-circuit when not in use and securely packaged?

BrankoDecember 28, 2007 10:21 PM

Croatian Airline has been prohibiting batteries of any kind in checked luggage for many years. I wonder if the reasoning is the same.

SeanDecember 28, 2007 11:00 PM

DOT Ruling on Primary Lithium Metal Batteries.

Incidents related to the rules mention anywhere from one battery to two whole pallets catching fire.

They're HAZMAT and therefore must be shipped under HAZMAT rules. Usually this stuff is not to be shipped on passenger aircraft. Fire on an airplane is a relatively insignificant problem and we haven't had problems with things like oxygen generators taking a jet out of the sky, eh?

AnonymousDecember 28, 2007 11:20 PM


"Doing something as simple
as keeping a spare battery
in its original retail packaging
or a plastic zip-lock bag will
prevent unintentional
short-circuiting and fires,"
said Krista Edwards, Deputy
Administrator of the U.S.
Department of Transportation's
Pipeline and Hazardous
Materials Safety Administration.

This is bullshit. I have not owned any Li-ion battery that had exposed terminals: they are all carefully recessed, and impossible to accidentally short together unless you are packing them with loose pins and needles. (I just reached up and checked some right now: Sony InfoLithium "L" 32 and 50 Wh packs and a Panasonic VW-VBG130 ~10Wh.)

And the reason for this is simple: laptop computer, camcorder, etc, manufacturers do not wish serious or fatal accidents upon their customers. The risk from these batteries has been well known to industry for decades, and been effectively mitigated to the point these power sources are almost ubiquitous.

How can it be that the government has suddenly found out right now? Didn't they figure out what the cause of that UPS fire was?

TomDecember 29, 2007 12:15 AM

I wonder if the fire extinguishers on board are capable of dealing with type D (metal) fires. I suppose the idea is that the battery would arc or get so hot from use that it would start a fire, but still.

AnonymousDecember 29, 2007 12:30 AM

@ Anonymous above:

You obviously have never handled a lithium primary cell, then. CR123A are the most common, but they come in other form factors as well... the design is a cylindrical cell with terminals on top and bottom, just like your familiar AA batteries.

MadtechieDecember 29, 2007 5:20 AM

These new rules seem to have been lifted from the existing UK (dating, I think, from 2006) regulations:

At the bottom of the page, this document:

The Carriage By Passengers of Batteries and Battery Powered Equipment

Contains details and a picture of aviation-related Lithium fires.

Heathrow has been displaying, for some time now, larger Lithium batteries in the glass display case of banned items.

There are differences in chemistry between straight Lithium and Lithium-Ion/Polymer regarding the amount of Lithium needed per WattHr of electrical capacity, hence the 2g and 8g different sections.

Unfortunately, in what is perhaps a bit of a knee-jerk rule, they've omitted the newest (and safest by far) type: Lithium Ion NanoPhosphate. Unlike the older technologies, this battery type has a non-flammable electrolyte and is essentially immune to the exploding/fireball Dell laptop failure mode.

There are videos on the web of fully charged LiFePO4 cells being shot, pierced by nails or having holes drilled through them - without dangerous failure modes.

Obviously such a concentrated source of energy can heat/ignite other materials, but that is far less hazardous than burning Lithium.

mozDecember 29, 2007 8:22 AM

> impossible to accidentally short together unless you are packing them with loose pins and needles

yes.. something like ... something like.. bits of metal connected together by other bits of metal... hmm... nope; nobody would carry such a stupid thing (let's call it "a set of keys" for the sake of argument) in their baggage. In fact, the best thing would be to simply ban the carrying of "a set of keys" in any form of baggage.
That would inconvenience far fewer people than insisting that spare batteries are properly packed.

Seriously though, most Lithium Ion batteries have very good protection against short circuits. This is true of anything for commercial use from a reputable manufacturer. However, many "alternative manufacturer" batteries come from countries with less strict liability rules and lack these circuits. I just recently discovered that one of my batteries was fake (when I realised that the serial number couldn't be used in a recall web page) and it is meant to be made by the company I worked for. The only sensible thing is to assume that many batteries will be dangerous if short circuited.

AnonymousDecember 29, 2007 9:46 AM

@ Anonymous above:

"You obviously have never handled a lithium primary cell, then. CR123A are the most common, but they come in other form factors as well... the design is a cylindrical cell with terminals on top and bottom, just like your familiar AA batteries."

Try and keep up please: the regulations in question are targeted at secondary batteries. Standard Li primary batteries -- which indeed have open terminals -- have been forbidden for many years.

AnonymousDecember 29, 2007 10:10 AM


"The only sensible thing is to assume that many batteries will be dangerous if short circuited."

The short-circuit protection I was referring to was not electrical, but physical. Simply put: wrapping the batteries in a ziplock will accomplish nothing, as it is impossible to take two or more of these batteries and short their terminals together. The connectors are designed so the terminals are recessed when the battery is removed from its socket. It is not possible to short the terminals with the help of a single conductor, for the same reason. The recesses are themselves small enough to prevent the common "short via a set of keys", "pocket of change", and other potential surprises arise from more than one conductor (and that was no accident). The only way is to pack the battery with a large collection of very thin pins or needles. Possible, but highly unlikely. If we must assume this level of stupidity, then air travel itself must be strictly forbidden since anything can be dangerous.

CipherChaosDecember 29, 2007 1:41 PM

This, of course, is more security theatre. After all, there's nothing in the world more dangerous than lithium batteries burning hot... :: sarcastic smirk ::

rjhDecember 29, 2007 2:31 PM

This is from the background section of:

Pipeline and Hazardous Materials Safety Administration

[Docket No. PHMSA-2007-27493; Notice No. 07-02]

Advisory Guidance; Transportation of Batteries and Battery-
Powered Devices by Airline Passengers and Crew Members


Over the past several years, we have received a number of reports
of transportation incidents involving various kinds of batteries and
battery-powered devices, including incidents involving passenger
airline operations. The most recent incident occurred on February 10,
2007, aboard a flight originating at JFK International Airport. Shortly
after takeoff, a fire ignited in a passenger bag stowed in an overhead
bin. Fast and appropriate action by the crew brought the fire under
control and prevented injury to passengers and crew. The flight crew
promptly extinguished the fire and the flight returned to JFK for an
emergency landing. Although the fire is still under investigation by
PHMSA, the Federal Aviation Administration (FAA), and the National
Transportation Safety Board (NTSB), preliminary reports indicate
batteries were involved in the incident.
Other incidents have occurred on the ground. Last May, we received
a report of a fire involving a spare lithium ion battery that had been
stowed in a passenger's notebook computer carrying case. A flight
attendant removed the burning case from the passenger cabin, and tossed
it onto the ramp, where the fire was extinguished by ground personnel.
On April 18, 2004, at Chicago's Midway Airport, a power drill with
an installed nickel cadmium battery activated while in checked luggage.
This caused a fire that spread to other bags on a luggage cart waiting
to be loaded onto a passenger aircraft.
In June 2003, we received reports that an overheated battery had
been discovered in a routine baggage inspection of a flight departing
from Logan Airport in Boston. The battery had been loosely packed in a
toolbox, along with various metal tools. We believe the heat build-up
was caused by short-circuiting when the battery's exposed terminals
came in contact with metal objects in the toolbox.

MartinelliDecember 29, 2007 10:52 PM

My boss is into flying electric RC models and had one of these 4 cell Lithium rechargeable batteries catch fire in his garage. Thankfully, he was home and his wife noticed all the smoke. His house could have burnt down from it torching itself and setting other stuff on fire.

GrendelDecember 30, 2007 12:15 AM

I'm really glad they finally got around to this rule. Most airlines have had rules regarding computers in checked baggage for years... unfortunately not many follow the rules. I've seen 3 bags in the last two years completely melt down due to Li-ion laptop batteries. Of course it didn't just melt their bags but all the bags around it. its a safety thing not a security thing. if you don't like please don't fly.

Aidan ThorntonDecember 30, 2007 7:02 AM

Martinelli: I believe the lithium cells used in RC models don't have the usual safety precautions that all consumer lithium cells have, in order to make them smaller and lighter. (They're also at risk of being damaged in crashes.) You're supposed to be very careful about how you charge, use and store them.

AnonymousDecember 30, 2007 10:03 AM


"if you don't like please don't fly."

Spoken like someone who doesn't have any batteries?

Anyways, please read the text of the rule. Note how it is carefully designed not to catch 95% or more of all passengers, which probably maps to 99% or more of all batteries.

In effect, the probability of an accident has been reduced from P (whatever it is) to 0.99P. Do you really feel safer?

And, just so you know, there isn't much operative difference between "safety" and "security". Especially in this case, since erstwhile security personnel will be enforcing these regulations.

Clive RobinsonDecember 30, 2007 1:39 PM

@ Anonymous ,

"And, just so you know, there isn't much operative difference between "safety" and "security"."

English is one of the few European languages where there are two seperate words "safety" and "security". It has always been difficult to explain the difference to Continental Europeans as they generaly only have one word that covers both issues.

PhilDecember 30, 2007 3:16 PM

I question this rule. Truly there may be (rare) instances that the cell may short circuit, or that the cell is defective. Both of these issues might be ameliorated with specific battery designs or battery carriers for airline use. Neither of which the TSA was thoughtful enough to provide. I think that the TSA did not provide an explanation as they did not want anyone questioning their rules.
Interestingly, I think this is more of a problem than someone trying to sneak a shoe bomb on an airline though.

Nomen PublicusDecember 31, 2007 5:09 AM

OK it's a good idea not to have objects than can burst into flame on a passenger aircraft. So, why are lighters and matches permitted?

This page is interesting...

It appears that the TSA "protected" the public by allowing the public to "surrender" over 11 million lighters in 2006. Now they changed the rules and we will no longer be protected from devices that hold volatile liquids and a trigger mechanism.

There seems to be no rhyme nor reason here but I suggest that the TSA is just saving money by not having to dispose of 11 million lighters a year. That many lighters implies about 370,000 litres of butane that has to be disposed of as hazardous waste -- that must be expensive. Even storing the lighters in an airport waiting for disposal will require special rooms and procedures, more expense.

Or did the TSA just throw them into the nearest dumpster?

DanDecember 31, 2007 4:54 PM

Show me one verified incident where a lithium-ion battery that was free-standing suddenly exploded. This rule is ridiculous!

Are you an a/v professional? Good luck!

Brian BoykoJanuary 1, 2008 12:58 PM

I don't know about lithium batteries - never had a problem with that. But I was taking some AV equipment.

However, when I was filming in New Zealand, I went through security quite a number of times with the exact same cargo.

I flew from Austin to Los Angeles to Auckland, then Wellington to Hamilton to Wellington, then Wellington to Auckland to Los Angeles to Austin.

On that final flight, Los Angeles to Austin, they told me that I could not take the florescent light bulbs on the plane with me. The scame flourescent light bulbs that I took with me on six previous flights...

Assaulted & BatteriedJanuary 1, 2008 6:23 PM

I'm about a week away from a trip expecting to take plenty of A/V and PC gadgets with spare batteries and got hit with this. I'm as confused as ever. How much Lithium metal is in a CR123a battery? And if a Lithium Ion battery is under the 8 gram limit does it still have to be counted in the two only spares? This sux Big Time.

Alan JJanuary 2, 2008 12:59 PM

It makes it easier to remember and comply with seemingly "random" rules when you understand the reason for the rule (then they aren't random). This is why the secrecy of the TSA's rules is such a bad idea.

ufofruitJanuary 2, 2008 6:28 PM

I am surprised that they have not put a warning on the batteries that reads:"Do Not Suck On Batteries.Poison.Unless
you have been diagnosed manic/depressive......"
In the 1970's my Dad walked onto a plane with a machine gun barrel for his son-in-law....

ActionJacksonJanuary 2, 2008 7:14 PM

The rules come from the FAA; no problem there. The reported crash or two (in addition to those defective "exploding" laptop batteries a while back) seems ample rationale.

And the TSA is the logical agency to enforce this, of's just their arbitrary behaviour that worries me.

It seems more likely they'll just confiscate all lithium batteries, no matter the size...or go the Croatian Air route and just confiscate them all "to be safe."

That will get expensive and unpleasant fast...

odin7January 3, 2008 12:28 PM

I just called the Energizer Corporation and directly asked if their "Photo 123" Lithium battery is banned. They said no, it contains less than 1 gram of Lithium metal, which is well under the 2 gram limit. So I believe if a CR123A battery is either installed or properly taped and individually wrapped, it can go on as carry-on luggage, but not in checked luggage. But then again who knows if the TSA inspector will agree. Energizer seems to be on the ball, you can get their 800 number on their website.

UPS FanJanuary 3, 2008 9:28 PM

You'll all quit whining as soon as the first lithium battery fire statistician gets his first taste of smoke inhalation, ideally, while his plane is still on the ground.

Concerned HamJanuary 15, 2008 10:50 AM

"Starting in 2008, there are new rules for bringing lithium batteries on airplanes. Near as I can tell, this affects no one except audio-video professionals."

Unfortunately, this isn't quite the case. This will certainly affect me as a ham radio operator and I'm sure many other type of folks. I mention ham radio operators as myself since we end up playing a crucial communications role during a disaster all too often (i.e. "When All Else Fails").Between spares for handheld radios, laptop, etc....this could be a real problem.

GauteJanuary 15, 2008 2:54 PM

Li-batteries were treated as explosives on military airplanes in the early eighties, and only put in our backpacks just before we jumped out. We only had them issued on one or two occasions due to the cost. Seems like the civilian authorities took their time to figure this out.

Wim TonJanuary 16, 2008 6:56 AM

Other malicious uses of batteries:

Throw the lithium in the toilet, where it will react with water to hydrogen. Wait till the correct air/hydrogen mixture is reached and cause a spark.

Short the battery of a power tool in the hold luggage. The shorting device can be made small enough to escape x-ray detection. Pack the rest of the suitcase with clothes as flammable as possible.

Concerned ebikerJune 27, 2008 6:35 PM

This effects more than audio/visual professionals. Anybody who commutes via electric will have some sort of battery and the newest safest battery to come as of yet is LiFePO4, a very popular battery for small electric vehicles(Bicycles, scooters, etc.). As a college student soon to be transferring, and needing to take an airplane for said transfer, I would be forced to temporarily depart from my energy-storage mechanism and instead using a shipping service which would probably deprive me of said battery at least 1-2 hours after the flight and cost me the shipping fee(Which actually isn't that much but, still, the principle: What's wrong with LiFePO4? It doesn't explode and it doesn't catch fire. Obviously this rule is too generalized.). I think it'd be nice to just get out the airport and then scoot my way to my apartment instead of being forced to take a rental car(Or, oh dread, a taxi) just to pick up my mail.

Ebiker No. 2January 21, 2009 5:47 PM

I too would like to take my Iron-Phosphate lithium battery on flights. This would make it possible to travel with my electric folding bike. LiFePO4 is a very tough chemistry, such that there can be no thermal run away. The battery management system that is attached to every battery prevents short-outs. It should be possible to take these batteries on flights. What can be done?

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