Cfrgtkky

In about 3 months I will be flying from Estonia (Tallinn) to New York (Newark) via Stockholm (Arlanda) by SAS. I have an Aukey 30000 mAh (~111 Wh) battery bank which I'd like to bring on board with me. I did some research and discovered that batteries over 100 Wh require approval by the airline. On my previous flight from Tallinn on British Airways I wasn't allowed to bring in the battery bank with me, and had to hand it over for storage.

I've contacted SAS customer service and they have given me approval (verbally, over the phone) to bring the battery bank on board in my carry on. They also say it's written somewhere in the booking notes, which the check-in staff would see.

However, how would the staff at airport security in Tallinn and Newark know that I'm permitted to carry it? Can they look up my booking and verify it there, or should I request a written approval from SAS to show security?

In short, they don't know, but they also (usually) don't care. There are three different things at play here:

1. 
   Airport security, run by the TSA and its equivalents in other countries. The TSA is fine with power banks. In some airports, you're required to take power banks out of your bag, but this is just to ensure that they're not bombs or something. (Of course, large lithium batteries actually make pretty impressive incendiary devices, but apparently no terrorist has figured this out yet...)


2. 
   Aviation authority rules, set by the FAA and its equivalents. This one is cut and dry in the US: FAA regulations prohibit carrying portable batteries over 100 Wh, although with explicit airline permission up to 160 Wh is OK. The EU has the same regulation.


3. 
   Airline rules, which each airline can set for themselves. In this case, you've received permission so you're good.

In practice, what's going to happen is that your power pack will (most likely) be waved through TSA security and allowed on board by the airline. In the unlikely event of being questioned, a printout of permission from the airline would be handy, otherwise you'll need to convince them to go talk to the airline and that seems like a hassle for everybody involved.

FWIW, I always travel with a 20000 mAh power pack and I've had somebody inspect the label exactly once, and that was in Beijing, which is rather infamous for really strict and often pointless security rules. I'm somewhat surprised to hear Tallinn did the same to you, but in my experience this really is the exception rather than the rule.

Update: Much to my surprise, the FAA apparently lets airlines allow up to 160 Wh, so amended accordingly.

Since I'm new I cannot comment directly on jpatokal's post. It is not the case that the FAA bans all battery packs above 100 Wh. As their own link states, up to two batteries above 100 Wh and up to 160 Wh are permitted onboard, with airline approval. Sometimes the airline approval is just provided carte blanche; sometimes it's provided with advance permission, as in your case.

Many countries's security are lax about this and don't check the capacity of the battery. China is one of very few places where I've had a security officer examine the rating on the battery.

China often looks at the units--and disallows not only anything that's over the limit but anything that isn't marked. (Presumably to keep people from erasing the markings and claiming it's under the limit.) Personally I have not had them inspect my battery but it's far below the limit, presumably they can see it's ok from the X-ray. I have had them find it in my checked baggage when it inadvertently got placed there instead of with my laptop where it belongs.

I would be a tidbit careful. Although probably nobody will care, whatever that guy on the phone told you is a violation of IATA rules. SAS, like almost every airline, is part of IATA.

Please refer to this document on page 7 which for the battery ("battery" as defined on page 4) that you have reads Pax A/C = forbidden, where Pax A/C means "passenger, adult or child"

So there's something that some mildly uninterested bugger who probably didn't even listen properly to what you said, who doesn't care anyway, and whose name you probably didn't even write down told you on the phone. And on the other hand side, there's an official document which explicitly says the opposite.

Might work out, might not.