Hacker News Reader

Comment by smeej | Hacker News Reader

I feel like I'm having some sort of Mandela Effect moment, but maybe I'm missing something a lot more obvious?

I've had portable charging battery packs for at least a decade. I wasn't special. They were common. But it's only in the last few years that I've been hearing any concern about the batteries in consumer electronic devices causing aircraft fires.

I remember hearing about the ones in hoverboards, and then there was one version of a Samsung device that had problems, but nobody generalized to "all such electronic items must be in the cabin with you, and if you lose track of yours, we're turning the plane around."

Did something maybe change about battery chemistry that I don't know about? Or did the design change, such that the batteries aren't protected anymore or have enough more capacity that they've become dangerous?

I can't imagine there were actually widespread battery fires for as long as I remember never having heard not to put a battery in checked luggage, so what else changed such that this is such a major issue now when it wasn't before?

View on HN

Devices are smaller and portable batteries are treated roughly. Also, many devices have batteries with custom-ish shapes that may be better or worse than standardized designs that were popular before devices get thinner.

The other thing is that consumers won’t be aware of risks for semi-disposable batteries. I found out a few days ago that a high capacity Anker battery that I own was recalled last year. Would such a thing even happen for a random battery sold at CVS?

I was in a leadership role for an org with about 95k laptops. We had, on average 4-6 significant battery incidents with an ignition per year. Anywhere from 30-250 reported battery swelling events annually. It’s enough that we provided kits for safe storage of at risk batteries to every field office.

Now that’s a pretty low risk of an incident, but in an airline environment the impact of that risk is very high.

I'm almost surprised that you had that few battery swelling incidents although I assume that in a corporate setting laptops tend to get refreshed before you're likely to have swollen batteries. I've had one myself in an Apple MacBook Pro but it was a pretty old model when that happened. (Also an older iPhone that was driving my stereo system when I went to replace it after doing an upgrade.)

I suspect there’s more swelling that we don’t hear about. Environment matters though. Phones and tablets with wide operating ranges (Samsung was rated for like 0-120 F) have higher failure rates outdoors than iPhones… but if you try to use iPhones in a hot parking lot in the summer or keep them in an outer pocket in the winter, they’ll shut down. (The device doesn’t break, but it fails for the user)

For laptops the target was 4 year replacement for most and 2 year for high performance. IIRC, there was a Dell model where the swelling and battery shape was such that the device was super wobbly and damaged that spiked the numbers. Most devices would just get tagged as a bad battery and repaired or replaced.

If I was still there or in that role, I’d collect more battery data in general, as it’s both an employee safety and perhaps a quantitative difference that can be leveraged in purchasing.

>it’s both an employee safety

Yeah, you know if a work laptop catches fire in someone's house, especially if there's appreciable damage much less worse, there's not only your concern for your employee's well-being but serious lawyers are going to get involved and your company is probably going to write a pretty large check to make it all go away.

Not lithium battery related but I recently had a built-in microwave control panel (apparently) decide to self-immolate at 4am. The fire department responded and I'm fine and the direct fire damage is relatively limited but smoke throughout house. The interior is emptied out, the interior is being redone to a significant degree, and this will be basically months of work and lots of money even given insurance. Wouldn't do wonders for my productivity over the rest of the year if I were still working full-time either.

Living out of hotel. Can't imagine the situation with young children and someone who can't write large checks even if they're partially reimbursed.

Was it a General Electric microwave? I had two that tried to burn my house down. I didnt know the first one was the same company.

What I did is not buy another microwave.

Samsung. About 15 years old but still shouldn't happen. "Funnily" enough as I vaguely recall, the competition was GE.

I'm getting countertop Panasonic 4-in-1. I'm getting rid of double ovens (the second of which I basically never used) in favor of a range, which will be induction in place than my prior propane cooktop.

i'm jealous. Hope your kitchen setup brings you much joy.

> more swelling that we don’t hear about.

I guarantee there is. Device quits working, user doesn't know why, they discard it.

My only swelling incident so far was on a makeup mirror my wife owns. The battery is in a compartment whose door popped off due to the swelling. She asked me only when she couldn't get it to latch again. I looked at it and immediately told her not to plug it in.

Despite the fact that this thing cost hundreds of dollars, and they do sell some spare parts, the battery isn't one - and the battery leads are soldered directly to the circuit board. After some hunting around for a compatible battery (size was a major restriction), I bought it (~$15), cut the connector off, and soldered it to the board.

I tried emailing customer service; never got a reply.

These numbers are sobering - thank you for providing. Even a single battery ignition incident can burn my house.

Most people get off with it, but after I found an old iPhone with a badly swollen battery (and put it in my fireplace; this was during the summer until I could properly dispose of it), I became much more cautious about keeping old laptops and the like hanging around the house for old time's sake.

I know I have some truly ancient stuff up in the attic for basically nostalgia and I should just recycle.

> never having heard not to put a battery in checked luggage

Maybe not conventional batteries, but you've been disallowed from putting lithium batteries in checked luggage for at least 16 years. I remember being dragged into the bowels of an airport by security to open my checked bag because I'd forgotten a device in it. That was in 2009.

When you check in bags they ask you to make sure there aren't any rechargeable devices or battery packs in them and this has also been going on for a long time.

I still send my AirTags in checked luggage. But they are small!

Checked baggage is actually one of the better use cases for AirTags.

AirTags also don’t use rechargeable lithium batteries.

Aren't non-rechargeable batteries still at least a little dangerous, though?

They're more dangerous. The reason lithium-metal batteries are "non-rechargeable" isn't that recharging them doesn't work; it's that they have an unacceptable probability of exploding during the process. Other forms of electrical, thermal, or mechanical abuse can have similarly spicy results.

Spare non-rechargeable lithium batteries are also forbidden in checked luggage[0]. AirTags are allowed because the battery is installed in a device, though Lufthansa briefly tried to argue otherwise after some bad press involving passengers finding their own lost bags[1].

[0] https://www.faa.gov/hazmat/packsafe/lithium-batteries

[1] https://arstechnica.com/gadgets/2022/10/lufthansa-awkwardly-...

When people say “Lithium batteries” in this context, they mean lithium-ion rechargeable batteries.

AirTags contain lithium primary batteries, which are a totally different thing (other than both containing the element lithium).

Lithium primary batteries present no more a risk than alkaline AAs. Probably less.

They are more dangerous. They contain significant amounts of lithium metal, the thing that bursts into flames when in contact with water. There are similar restrictions on them for air travel.

> They contain significant amounts of lithium metal, the thing that bursts into flames when in contact with water.

How does that tell you that they are dangerous? The danger with rechargeable Lithium batteries isn't that they contact water and begin to burn.

Last time I ordered some lithium primary batteries from Amazon it came with the lithium sticker. I didn't look into the rules.

Lithium poses two risks:

1) The internal resistance is low enough that if it's shorted it can go into thermal runaway. This is the risk they had in mind when saying no loose cells (but note that cells merely need to be securely contained, not specifically in a device.)

2) Secondary cells can grow whiskers inside the cell. If a whisker grows just wrong it can short the cell from inside and drive it into runaway. This is the risk that they are worried about here--and it's a legitimate risk, it's brought a plane down.

The reason the rules are different in the passenger compartment is that while there's nothing on board an airplane that can fight a lithium fire it's generally a small, weak fire (the big e-bike batteries that have been in some rather dramatic videos aren't allowed) that humans can generally keep from turning into a big fire. But if nobody can fight the fire you have a big problem. Hence why lost phones are treated very differently--they could have fallen someplace where the fire wouldn't be fought.

Yeah, I’ve been aware of this for ages. That said I’m sure lithium batteries in checked luggage are super-common in things like electric razors and tooth brushes and a ton of other things we never think about.

It’s like airplane mode. How many cellphones on a given flight are actually in airplane mode?

A phone not in airplane mode and a high capacity lithium battery are not comparable at all.

Airplane mode is largely pseudoscience/an abundance of caution/solving a different problem than a safety one. There's approximately zero chance of a phone interfering with avionics, especially modern ones, with their very low transmission power.

Supposedly the real reason has always been that mobile network operators don't like the interference high-altitude phones can cause: They're in view of potentially many base stations, some of which might be using the same frequency (which is possible since far-away regular-altitude phones are below the radio horizon and therefore not an issue).

Some evidence for this theory: The "mobile phone ban" is an FCC regulation, not an FAA one, and many (non-US) airlines have been offering on-board microcells for decades without any issues.

"the real reason has always been that mobile network operators don't like the interference high-altitude phones can cause: They're in view of potentially many base stations". This makes zero sense: the aircraft is on the ground and not moving when the ban is put in place. The ban is removed at altitude, when, you say, that the phones are potentially 'in view' of many 'cell towers' (not base stations). In fact, the plane is essentially a Faraday cage at altitude, and a phone has almost zero chance of connecting to a tower, even shoved into a window pocket.

> The ban is removed at altitude

Not in the US, where it applies throughout the flight.

And at least in Europe, the ban is due to the risk of distraction/disorientation in case of an emergency, in my experience.

> the plane is essentially a Faraday cage at altitude, and a phone has almost zero chance of connecting to a tower

Counterpoint: I have a whole collection of “welcome to <place>, your roaming charges will be <exorbitant>” text messages on my phone from countries I’ve only ever overflown at 30k feet.

This is from flights that do permit in-flight phone usage, but I believe my network has no roaming agreement with the microcell operator, so it keeps scanning and sometimes catches a bidirectional link to some long-range tower. (They’re specifically optimized for that in the North Sea and Atlantic for fishing boats, as far as I know, so for regular modern towers it’s probably less likely, but that separation hasn’t always existed.)

Supporting your counterpoint: I am a cell tower geek and I have an app on my phone that records the cell ID of every tower my phone attaches to. I once flew from Wellington to Auckland on an Airbus 320 and forgot to turn off Airplane mode. Arrived into Auckland and my app had logs around a hundred or so cells my phone managed to attach to. So it can happen. I've also had successful two-way text conversations while still in the air but low enough (e.g. when descending on approach to an airport). Saying a plane is a Faraday cage is a bit extreme but I do acknowledge the steel tubing around you will reduce the signal strength by quite a bit -- but not quite enough to 100% block out the signal it seems.

Plane windows are large compared to radio waves. They'd need to be no more than about 5 cm wide to create a full Faraday cage.

Supporting your counterpoint too: MH370 co-pilot's mobile phone did connect to a cell tower mid-flight after the hijacking. [0]

[0] https://www.dailymail.co.uk/news/article-6839167/MH370-pilot...

Is a lithium battery installed in a device (allowed) comparable with a lithium battery not installed in a device (not allowed)?

That's the steelman version of the parent poster's question.

Danger probably primarily varies with capacity, production quality etc., not form factor (disassembled or assembled into a device), sure.

I'm not saying that current regulations of lithium batteries make sense; my argument is that the actual threat from lithium batteries seems larger than that of devices not in airplane mode (i.e. somewhere around zero).

An installed battery will have its terminals protected and connected to the device.

An uninstalled battery will have its terminals exposed, where they could be accidentally shorted by a stray paperclip, foil wrapper, or zip.

There's also the issue that the burden is on proving they're safe--and nobody has a reason to shell out the bucks to do so.

I do agree that interference is quite relevant. The general rule of radio is that you play nice, especially when on a licensed frequency (the cell companies have the licenses for those bands, the users do not), and a phone up high over multiple cell towers is most certainly not playing nice.

Small Li-ion batteries installed in a device are allowed in check luggage.

Loose/spare Li-ion batteries that are not installed in a device, and large batteries over 100-160 Wh are banned in checked luggage.

It's unclear to me what the official requirements are. For example this is from the TSA's site:

"Devices containing lithium metal or lithium ion batteries should be carried in carry-on baggage. Most other consumer electronic devices containing batteries are allowed in carry-on and checked baggage."

Taken literally, this is of course widely ignored. There are also various requirements around spare batteries that do include capacity limits.

> When you check in bags they ask you to make sure there aren't any rechargeable devices or battery packs in them and this has also been going on for a long time.

Literally never once have I been asked that and I flew internationally 6 times a year for more than 5 years.

The only thing I can think of is maybe you look like the kind of person that would have rechargeable devices and battery packs in his luggage? :)

Before you accept your plane tickets you get asked question about illegal hazards you are flying with. Lithium batteries are clearly noted. Maybe you are just skipping that notice because you assume you are not a hazard? :)

This definitely happens stateside. Usually during check-in

They had to pull my checked bags once because I couldn't find an 18650 when they asked me about carry on batteries for a puddle jumper the last time I flew, which was nearly a decade ago at this point. They definitely care. The passengers are also supposed to care.

People who don't care are the reason I don't fly anymore.

I see a warning about rechargeable batteries in checked in luggage almost every time I check into a flight. I wonder what explains our difference of experiences. Maybe it's the fact that I mostly do electronic checkins vs just showing up at luggage drop off.

Luggage drop-off asks the same question, here in Australia anyway

I also see this every time I check in for my Air NZ and Jetstar flights here in New Zealand. But I suspect like many I just by habit press 'No, I don't have any hazardous things to declare.' to move to the next stage of the check in process as quickly as possible! There are also signs and stickers on check in desks for those checking in manually -- but not sure how good the agents are at bringing people's attention to that.

I do get pulled aside for "enhanced screening" consistently while transiting Europe :-)

I'm sure you didn't actually mean it that way though :-)

A sibling comment made me recheck the rules and it does seem like phones and other small rechargeable devices are allowed in checked baggage.

Maybe I've been unconsciously extending "power banks and rechargeable batteries" to also mean device when questioned.

Except that one time in Latin America where they would only let me put my ultra-compact camera in checked baggage if I took out the batteries.

> “you've been disallowed from putting lithium batteries in checked luggage for at least 16 years.”

This rule only applies to loose (spare) Li-ion batteries, not batteries which are installed in a device.

Batteries over 160 Wh (in some cases, 100 Wh) are banned whether they’re in a device or not, but that’s far bigger than any phone battery: an iPhone 16 Pro Max battery is about 16 Wh, and typical laptop batteries are around 60 Wh.

IATA Li-ion battery fact sheet: https://www.iata.org/en/iata-repository/pressroom/fact-sheet...

Notably the 16” MacBook Pro (every model since 2019) goes right up to the 100 Wh limit.

For comparison, 100 Wh is 360,000 joules, which is just under either the energy released by explosion of 100 grams of TNT, or the kinetic energy of a small car at highway speeds, or the kinetic energy of 1 gram meteor hitting Earth.[1] (Sorry, I've never been a fan of the "Wh" unit and so wanted to put that total energy into layman terms.)

[1] https://en.wikipedia.org/wiki/Orders_of_magnitude_(energy)

Or a McDonalds medium fries?

EDIT: doh, just realised you were comparing with other forms of damage. That said, I think its truly amazing that a snack has the same energy as a nasty car crash. Mind blown.

That is, 100 Wh = 86 kcal.

Enough energy to heat 1 kg of water by 86°C (or 86 kg of water by 1°C).

To me it is hard to visualize how much damage the total energy gained from digesting chemical bonds of food could do to an airplane. I can better visualize the damage that could be done by a highway car crash or detonating a handful of TNT in an airplane.

These counterfactual comparisons are a slippery slope and not as helpful as you think. I hardly think that you, I, or most others have an intuitive understanding for what happens when a 1 gram meteor hits earth. Have you ever witnessed that?

The average failure state of a battery is not similar to detonating a handful of TNT on an airplane, which is a more instantaneous explosion. Sure, some battery failure states are violent and would unquestionably be a cause for an airplane to call a mayday and land, but something like puncturing a soft-cell battery is still a slower release than TNT.

We should just expect people to get better at understanding useful units — I'd prefer someone learns Wh since it is indeed a useful metric—kWh is the usual major unit of energy at home, and Wh is just smaller than that.

I was trying to guesstimate a theoretical upper-bound on the damage. Looking at youtubes online, it seems a labtop battery explosion is still scary and more like a handful of firecrackers than TNT, but what actually seems worse is that the explosion is followed by the labtop being on fire and producing subsequent smaller explosions. So the worse case is that the fire ignites other stuff in the plane, which includes other lithium batteries.

Can the battery actually release that energy as explosively as the TNT can? I mean under normal corcumstances, not maliciously modified.

(100Wh / 3.7V ~= 27000 mAh, 160Wh / 3.7V ~= 43000 mAh. Wh represents theoretical total energy, used as a normalized comparison, and Ah is used to practically determine max safe charge/discharge rates)

This rule only applies to loose (spare) Li-ion batteries, not batteries which are installed in a device.

I've heard of people ordering 18650s online and getting them along with a free flashlight in which they came; I wonder if this regulation is why.

Almost definitely for import tax/restriction reasons. Putting the battery inside a cheap flashlight places it in a separate category than a battery by itself. Felt on the bottom of Converse sneakers to classify as slippers is a classic example of this.

The battery limit described is for individual passengers, not air freight.

Air freight for Li-ion batteries is pretty strictly regulated too, especially when the freight is carried on passenger aircraft.

See UPS Flight 6 for a very good reason about why the flight of lithium batteries is regulated

As always, Admiral Cloudberg has a deep-dive into this crash: https://admiralcloudberg.medium.com/alone-in-the-inferno-the...

Slightly off topic, but she does an amazing job.

I watched both Mentour Pilot and Green Dot Aviation's videos about it. Mentour Pilot's video terrified me, as it simulated the audio of being inside the cockpit, with GPWS, fire warnings, the sound of the fire all going on at the same time

Green Dot Aviation: https://www.youtube.com/watch?v=T7uw6VzWHcM

Mentour Pilot: https://www.youtube.com/watch?v=Y50saxfTqQA

Yup, any time I order anything from Amazon that has lithium it comes with a big warning sticker about shipping restrictions. Even if it's a fixed battery inside a device.

Indeed. If it’s sold as already in a device, it doesn’t need the battery sticker and in general the regulations around shipping it are significantly less onerous.

many laptops are reaching 100wh limit, dell xps 16 has 99.9wh iirc

And people dont travel with single device anymore. My usually setup has 72wh powerbank, ~20wh phone and 90wh laptop, and various smaller gadget. They are reaching nearly 200wh

Interesting, at the airport I always see general "no (devices with) batteries in checked luggage" signs.

One time I had an old phone with battery removed in checked luggage and when I arrived at my destination, I saw they fiddled with the tsa lock and the phone was taken out of the envelope I had it in and just lying on top of my clothes. I mean maybe they saw it in an xray and wanted to steal it and then saw it was some old junk phone, no idea how good the xrays come out to tell beforehand whether you're dealing with an iPhone or 7 year old android midrange...

I also thought the reason you couldn't travel with unattached spare batteries was because something could bridge the + and - and create fire from a short, not because they were lithium. Like, traveling with my little power bank wasn't an issue because it's all enclosed.

Yup, it's happened to me. I had put the battery in my daypack while we were there. I thought it had gone back in my laptop bag for the flight--nope, it was buried in the daypack. PVG security caught it.

https://apnews.com/article/russia-poland-germany-sabotage-ca...

November 5, 2024

> WARSAW, Poland (AP) — Western security officials suspect Russian intelligence was behind a plot to put incendiary devices in packages on cargo planes headed to North America, including one that caught fire at a courier hub in Germany and another that ignited in a warehouse in England.

> Poland said last month that it has arrested four people suspected to be linked to a foreign intelligence operation that carried out sabotage and is searching for two others. Lithuania’s prosecutor general Nida Grunskiene said Tuesday there were an unspecified number of people detained in several countries, offering no elaboration.

People have been sending explodey batteries by air freight. In that context, requiring batteries on a plane to be in the cabin where they can be located, accompanied by the owner of the battery could be a good deterrent.

The IATA rules are actually quite permissive (Delta for example) for checked luggage:

> Lithium cells or batteries power many consumer electronic devices and medical devices, like watches, laptop batteries, calculators, cell phones, hearing aids and much more. You can bring lithium-battery powered devices as carry-on items or in checked baggage. Spare lithium batteries are allowed as carry-on items only with batteries individually protected to prevent short circuit.

FAA general rules are similar. The concern nowadays is that someone will drop a device into a seat mechanism and it could crush the battery.

>The concern nowadays is that someone will drop a device into a seat mechanism and it could crush the battery.

I took a few flights in the last year or two and they made an announcement along the lines of "If you happen to drop your phone between your seat, do not try to retrieve it. Call a flight attendant for help." Latest flights didn't make the same statement, but wasn't necessarily listening for it.

United at least seems to make this announcement on a routine basis.

> I can't imagine there were actually widespread battery fires for as long as I remember never having heard not to put a battery in checked luggage

This was pretty much the initiating incident, 15 years ago now: https://en.wikipedia.org/wiki/UPS_Airlines_Flight_6

This. The rules got tightened right up when this happened, because regulators basically looked at it and went 'holy shit, what if that had been a passenger aircraft?'

My wild ass guess: prices dropped, causing battery packs to get bigger and increase availability to people who may not understand or care about the risk. Additionally, with lower base cost of lithium ion batteries, you get more cheap crap that is not engineered well.

I think the proliferation of power banks is also relevant. More and more people have come to consider a power bank + cable to be normal travel gear. High energy density (it's not surrounded by equipment meant to be powered from the battery) and people often cheap out figuring the cost of a bad one being low.

Part of I feel like is that 10-15+ years ago, people only owned a couple of items with rechargable lithium batteries in them (if any at all!), and now people can have dozens. So the tiny chance of having one catching on fire is just multiplied by 10-20x just because there are many more of them around.

The other thing that was mentioned was that devices got thinner so there's a bit more chance of bending, squashing etc. stressing or puncturing the battery which can cause a fire.

And thirdly I think is cheap devices that don't have adequate protection against thermal issues etc., but that's mostly a risk during charging (that's where those hoverboard fire stories came from).

> one version of a Samsung device that had problems

The best GTA mod: https://www.youtube.com/watch?v=0IVk8PsSgEI

It’s just that when something hits a process there’s a massive step change as everyone normalizes processes around it. Until that moment, rare events are all that you see.

> Did something maybe change about battery chemistry

I don't think there's been any single notable change, but energy density is steadily increasing.

more things have lithium batteries now and questionably manufactured devices that aren't properly certified are as well

incidents with lithium batteries on US aircraft now happen about twice a week

there has been slowly ramping up concern about lithium batteries over the last several years as a result

I used to pack my laptop in my checked bag because I hate dealing with carry-on.

Note 7 introduced a lot of people to spicy pillows, it launched in 2016

Have you heard about the pagers in Lebanon?

it’ll be the beginning of a campaign to buy US batteries rather than ‘cheap explosive’ Chinese ones

Cheap lithium ion batteries are awful, though, so if the US ones are better, I'm for it. Like I know Westinghouse doesn't manufacture their own l-ion batteries, they use white label from some manufacturer they trust, probably LG.

But I have thrown away probably 100 18650 and 26650 batteries that just sucked or were fire hazards.

The cheap junk *should be* banned as a fire hazard.

Reply on news.ycombinator.com