Can I take a LiFePO4 battery on an airplane?

Wed Nov 29

Written by: Casey O.

Yes, probably, depending on the size and only in carry-on, but there is some fine print.

This article is not advice, just a collection of rules and experiences surrounding taking LiFePO4 batteries on airplanes. In the end, a TSA agent will make the call. Attempt at your own risk, keeping in mind that they might be confiscated.

As for the rules, here is what the TSA says:

Lithium batteries with more than 100 watt hours

Spare (uninstalled) lithium ion and lithium metal batteries, including power banks and cell phone battery charging cases, must be carried in carry-on baggage only.

With airline approval, passengers may also carry up to two spare larger lithium ion batteries (101–160 Wh) or lithium metal batteries (2-8 grams). […] There is a limit of two spare batteries per person for the larger lithium ion batteries described above (101–160 watt hours per battery…

There seems to be fewer rules about batteries under 100Wh.

For larger batteries, it depends on the airline. For example, Delta allows up to two batteries under 160 Wh:

Passengers are permitted to travel with lithium ion batteries that contain a maximum of 160-watt hours per battery. […] Lithium ion batteries not installed in a device (spares) must be in carry-on baggage and no more than two (2) spares between 100 and 160-watt hours are allowed.

In addition, here is a good guideline that Delta provides:

I’ve attempted to bring a LiFePO4 battery on airplanes two times. Once it was confiscated, and once it passed.

My first attempt saw my battery confiscated. I had packed a 12V 12Ah LiFePO4 battery (153.6Wh) in its original packaging in my carry on luggage. The TSA agent told me that the limit was 100Wh. I tried to explain that the specific airline I was flying with allowed up to 160Wh. They checked with their supervisor, but in the end told me that they couldn’t let it through.

For my second attempt, I had more luck. Again with a single 153.6Wh LiFePO4 battery. I took a few more precautions this time. I printed out both the TSA and Delta’s rules about lithium batteries above 100Wh, just in case. The battery was packed in its original packaging, which included plastic covers on each terminal. I had the battery in a shopping bag, with some snacks. I thought it would be easier than pulling it out of my carry on. When the battery passed through security, it was pulled aside for to be checked. The TSA agent told me that packing batteries with food in the same bag was a big red flag, and that in the future I should not put food and batteries in the same bag when going through security, as it could seriously hold up the line. I showed him the size of the battery which was clearly printed on both the packaging and battery itself, and he let me through.

So, to review here are the steps I will take in the future: