Lithium batteries are banned in checked luggage. You're supposed to carry them on.

Well I've been lucky then! I've never packed my batteries with my carry on. What do you do with Di2? Or is it gotta be easy for TSA to care - no one is going to pull it out of your seatpost. Guess that is true with my toothbrush battery as well - which now makes me realize I've never once paid attention to this and have absolutely no idea what type any of my batteries are.

I feel for the OP! Man, that sucks. Hope he finds some batteries!

Sorry about your batteries.

TSA can be so freaking annoying with their wishy washy rules. I went on a bike trip and specifically asked TSA if I could bring a particular tool in my carry on. Both of the TSA agents asked me what it was for, I told em, and they were like “I don’t see a problem with that”. So, I figured I’m good to go. Flight home, different story. TSA agent pulls the tool out. I tell him the TSA agents at the other airport let me fly with it and he said “not in my shift” and threw it in the trash bin.

Besides that, they destroyed a shifter on a packed bike, as well as a rear derailleur. Despite me taking a lot of time to safely pack my bike, I open it at my destination and it’s like a tornado hit the insides.

Happened to me flying to south Africa. Got all the way there then a local flight took all my Allen wrenches from me... said I could take the plane apart from the inside.

I laughed... they threw them away. Had to go to a LBS to put my bike back together.

https://www.faa.gov/.../more_info/?hazmat=7

thanks for the link...I wonder if they have more than 2 grams of lithium. total weight of the battery is 24 grams. Regardless, next time I will carry them on. Surprised at the variability of TSA screening folks.

I had my DI2 battery removed out of seatpost in China.

Did you tell them it was a battery?
Cuz a di2 battery in a seat post doesn't look like much.
No f'ing way I'm going to remove my battery from my seat post to travel. Maybe I'll figure out a clever cap to hide it.

If they xray your bike case, they will see the battery.

TSA has always x-rayed my bike case and haven't said anything.

No I didn't tell them. I checked the bike in. I was about to board the plane and a police officer walks up to me, asks me if I'm Mr......I say yes, he pulls the battery from his pocket and hands it to me. With a form/note in Chinese.

I suspect this will become more routine in North America with time.

Last time I travelled with my bike to South America, I left my battery in the post and hand carried a spare. No incident.

I have travelled dozen of times with my DI2 battery. So far 2 "incidents", both in China, both resolved by removing the battery.

The 2 g limit is for disposable lithium batteries. For rechargeable lithium ion batteries..."Lithium metal (non-rechargeable) batteries are limited to 2 grams of lithium per battery. Lithium ion (rechargeable) batteries are limited to a rating of 100 watt hours (Wh) per battery." I'm still on mechanical shifting. What is the battery capacity of Di2 and other batteries for electronic shifting?

Yup, I used to fly pretty often to mountain bike races, I had a backpack that I would carry on with shoes, helmet, kit and a couple tools that just stayed in the backpack. After probably 20 flights I was told one of the wrenches was a quarter of an inch over the limit and they took it from me.
I was also once told that having my helmet clipped to the outside of my backpack put it over the carry on size limit, so I boarded the flight wearing said helmet as a hat. I left it on for take off and put it back on before landing and told people I was a nervous flyer.

I lost my Park Tools 3 way bicycle hex wrench to South African security. It had been all over the world in my backpack until there.