Q: I’m traveling soon and plan to bring all the devices I usually use, including my smartphone, tablet and laptop. What should I buy to keep everything charged? A: If you’re traveling domestically, one large and one small power bank plus a foldable charging station (in addition to your usual cables and wall adapters) should keep your devices reliably powered. If you’re heading to another country, you should also include an outlet adapter. And if you’re flying, there are a few TSA rules you should know about that apply to electronics and external batteries. How to pick a power bank for travel Over the past few years, I’ve tested dozens of portable batteries for Engadget’s guide to the best power banks and I’ve brought a bunch with me on planes, trains and interminable automobile rides. My go-to battery right now is Anker’s Laptop Power Bank, which I only rarely use for charging my laptop — it's far more versatile than the uncreative name may suggest. I also have a couple of smaller banks to grab when I don’t need quite so much charge. The three important features to look for when picking a portable charger to take on your travels are its capacity, weight and connections. Capacity Most portable chargers list their capacity in milliamp hours (mAh). Anything less than 5,000mAh is pretty useless — it won’t even get a smartphone up to fifty percent. I recommend looking for a power bank with 10,000mAh or higher capacity. One thing to note is that there’s not a one-to-one correlation on capacity: a 10,000mAh power bank will not refill your smartphone’s 5,000mAh battery twice. Voltage conversions, heat loss and the operation of the battery all cut down on the amount of charge delivered. Weight This is directly related to capacity. Just about every 20,000mAh battery will be heavier than a 10,000mAh battery. If you’re really concerned with keeping down the pounds and ounces in your luggage, you might want to pick the smallest capacity you think you’ll need. That said, the largest TSA-compliant batteries are 27,000mAh models, which weigh between two and 2.5 pounds. That may or may not make a huge difference in your packing scheme. Connections The last thing to look for is the right connections. Every power bank I’ve tested has at least one USB-C port. Since you can get a USB-C cable with just about any connector at the other end, that should cover what you need. But if, for example, you have an older smartwatch charger with a USB Type-A connector, you’ll want to make sure your power bank has that slot. You’ll also want to remember to pack the right cables for each device. I’m seeing more banks with built-in cables, which is convenient, but you’ll probably still want to bring a couple extra cords just in case. How to fly with charging accessories Current TSA and FAA rules say that all spare batteries, including power banks, can only go in your carry-on luggage, not your checked bags. They must be rated at 100 watt-hours or lower, which in most batteries translates to roughly a 27,000mAh capacity. That capacity range covers most portable power chargers out there, since most manufacturers want their banks to fit within travel recommendations (larger batteries are often marketed as portable power stations). There’s no limit on the number of batteries you can carry, but they should be for your personal use and must be protected from damage. Items like fast chargers, wall adapters, cables and regular alkaline batteries (ie. AA and AAA cells) can fly in either your checked or carry-on luggage. Of course, as with all TSA regulations, the final determination of what you can and can’t bring with you lies with the agents themselves, but this advice follows the agency’s current guidelines. If you’re flying internationally, you’ll want to check the baggage policies of the airline and airport you’ll use for your return flight. A quick check of International Civil Aviation Organization (ICAO) policies and the five highest-trafficked non-US airports (Delhi, Haneda, Istanbul, Heathrow and Dubai) shows that similar rules apply: spare batteries must go in carry-on bags and can’t be checked. A few policies put the upper capacity limit for external batteries at 100Wh, but the ICAO actually allows banks up to 160Wh. Have a tech question you’d like Engadget to answer? As tech reporters, the Engadget staff is always answering questions from friends and family about electronics, software, gaming, big tech policies and more. So we decided to write down our answers. This question is a composite of ones we’ve been asked recently. If you’ve got a tech-related question you’d like us to answer for you, please email ask@engadget.com.This article originally appeared on Engadget at https://www.engadget.com/computing/accessories/ask-engadget-how-do-i-keep-my-electronics-from-dying-when-i-travel-110022879.html?src=rss