Travelling with Lithium Batteries

by vk3arr

Having just completed a long trip carrying a Lithium Iron Phosphate battery, I’d like to share a few key points in case anyone else is planning to do the same. This will hopefully protect the investment you have placed in your batteries, and enable some good SOTA at the other end.

Note: This advice is based on my own experience and is by no means intended to be authoritative or canonical. I take no responsibility for any loss you may encounter by following this advice, and you must complete your own research before travelling with lithium batteries. Different countries and different airlines have different rules on this stuff. Do your research.

I flew with Qantas via Dubai, then Japan Air Lines through Tokyo. I cleared security at Melbourne, Dubai, London Heathrow and Tokyo Narita airports. Based on those airlines and IATA, I found the following out:

  • Lithium batteries are classed as a dangerous good, and appear prominently under the “batteries” section of the dangerous goods list. This probably means you should declare them to the check-in staff when you check in. I didn’t, firstly because I forgot to, but largely because I knew the rules for the airlines I was flying.
  • Lithium batteries must either be installed in the device they are powering, or, if spare, carried in your carry-on luggage only. I have never checked a lithium battery in, and always carry them onto the aircraft. If installed in the device, you can carry a battery up to 160Wh in capacity, or 2g of Lithium content.
  • Lithium batteries outside of the device are classed as “spare” batteries. If you are carrying a spare battery, you can carry up to 100Wh of batteries as spare batteries for a device, or 2g of Lithium content. You can also ask for permission from the carrier to carry spare batteries up to 160Wh in capacity, but this must be done in writing before you check-in, so cannot be done at the check-in counter.
  • Lithium batteries must be transported in a manner that prevents short circuits.
  • Lithium batteries may be subject to additional screening.

OK, so those are the rules. How do we apply that in practice?

  • What sort of battery are you taking? Not all Lithium batteries are equal. Li-Ion batteries such as laptop batteries are a different chemical beast to Lithium Polymer (LiPo) batteries and Lithium Iron Phosphate (LiFe).
    Follow the basic rules for each chemistry in terms of transporting. You want to keep LiPo batteries in a “fire safe” bag. I personally would be concerned about boarding an aeroplane with anything that requires transportation in a fire safe bag, so I recommend not taking LiPo batteries on an aeroplane. See YouTube for many exciting videos of LiPo batteries catching fire.
  • What battery are you taking? Look at your battery. It has many parameters on it, but probably not a Watt-hour rating. It will have an amp-hour rating on it, and maybe a voltage too, but it may not, having only 3S or 4S stamped on it. It will probably not have the grammage of lithium stamped on it.
    For LiFe batteries, 4S is 13.2V, which is an almost perfect swap for a 13.8V SLAB battery. I have two 4S LiFe batteries, one 8.4Ah and one 4.2Ah. The 8.4Ah battery therefore has a watt-hour rating of 13.2×8.4 or 110.88 Wh, above the magic 100Wh mark. It stayed at home. The 4.2Ah one is obviously half of that, or 55.44Wh. I took that one, rather than going through the rigmarole of getting the 8.4Ah approved.

    Note that there is a restriction too on the lithium content in the battery. I could find no reference to tell me what percentage of the battery is lithium or what weight that corresponds to. Instead, I note that the 2g limit also applies to 160Wh batteries, so I’m guessing unless you are using an exotic lithium chemistry, you won’t exceed the 2g limit. If you don’t know, the security staff won’t know either 🙂

  • How do you package the battery? Firstly, I have my LiFe batteries with the original 5.5mm bullet connectors on them, with an adaptor that provides Anderson DC connectors for connecting to the radio. I taped (using duct tape) each joint between the adaptor and the bullet connectors, as well as taping the ends of the Anderson connectors for good measure. I then put the battery into a zip-lock back and placed it into my carry-on luggage.
    Double taping, plus taping the Anderson connectors may seem like overkill, but you are trying to demonstrate that you are avoiding short circuits that might cause the battery to overheat. The plastic bag also helps serve this purpose. When I travel for work, I put my laptop battery (Li-Ion) into a zip-lock bag and do not bother taping the terminals, but a laptop battery looks very different on an X-ray to a LiFe battery. It’s better to overreact where LiFe batteries are concerned and keep security calm.

    Finally, consider where in your bag you put the battery. The TSA have a good bit of information on packing your carry-on to avoid a cavity search whilst traversing America. Search their website. I kept my battery to one side of a middle section, in a pocket where it was unlikely to move around. I carried a DSLR, laptop power and noise-cancelling headphones, all positioned to avoid obscuring the X-ray image of the lithium battery. It may have had the desired effect (I didn’t get cavity searched), or it may have been pointless, but in my experience, travelling with lots of wires floating about at random is a good way to get enhanced screening.

  • How does enhanced screening work? Lithium batteries may be subject to further security checks. This happened to me at Dubai and at London. In both instances, keeping calm and knowing airline policy helps. In Dubai, they were worried about two things – a weird reading that turned out to be a pinion gear in the lens of the camera, and the battery. The battery left my sight and was taken for further scans. It came back with no problems.
    In London, the battery was the only thing that was picked up for scanning. Remember the fact you have it in a plastic bag? They can just remove that and recheck. Makes their life easier. It helps them understand that you understand how to travel with lithium batteries. These two things make you less of a risk, so they treat you nicely. I answered a few questions about the battery and the device it was a spare for. It went through the X-ray again, and I was free to go.

    This also is a good reason to not travel with LiPo batteries. Imagine the look on the face of the security screener who pulls out a bag marked “fire safe” for an item he’s already had flagged by the X-ray operator. It might not hurt, but can’t see how that’s going to help either.

    I haven’t travelled through America yet with a LiFe battery, but frequently with a spare laptop battery. I’ve had my bag rescanned once, but as long as you’re calm and positively perky about the idea your bag needs to be rescanned, the TSA is pretty cool. My theory is most people who get tagged for, ahem, enhanced patdowns are those that get uptight and freak out. The TSA are just doing a job, and didn’t want to touch your private parts any more than you want them to. The law’s an ass and they just had to touch yours. If you have an attitude of “Air travel is fun!” even if it’s your third connecting flight after 23 hours, they respect that.

  • Know your rights Usually that statement is meant to convey a sense of standing your ground in the face of over-officious security or check-in staff. I don’t mean it in that sense. I mean understand exactly the requirements of each and every airline you are flying on, and each and every country you are traversing. Remember that even transit areas can have different rules to the airlines, and these will trump any airline permissions. I had a sudden fear of this in Dubai – I hadn’t researched Dubai’s rules on carriage of lithium batteries. But, I also knew that if they took it and I asked them under what grounds, they’d give me an answer and I could go from there.
    Make sure you carry copies of the airline’s policy on carriage of lithium batteries to help your cause. I didn’t need to pull my copies out at any point on my trip, but knowing I had Qantas’ and JAL’s policies handy meant I knew I had a better bargaining position. At the very least, the security handler would probably call his supervisor over rather than just confiscate the battery.

So, that’s my basic advice, based on my own experience. I will probably have to travel to the US sometime this year, at which point I will probably try going through TSA security with a LiFe battery. I will report on how that goes.