Unable to charge laptop on airplane

Hardware and technical stuff
1

I have an ASUS ROG strix laptop. It’s charging brick says:

Input
100-240v 50-60hz 3.2A

Output
19.5v == 11.8A

I flew many flights over past 10 days on American and Alaska and their AC chargers provided by the seats will not power this brick.

Reading about it online, I need something that will draw less power.

Right now, this laptop lasts maybe 1.5hrs. I realize another less powerful charger may not charge it fully, but maybe I can get another hour out of it before it dies? Or at least be able to charge it when it’s not in use (I had a 6hr flight from PDX to Miami).

Anyone else run into this?

I contacted Asus tech support and they were zero help. When I asked for an ASUS compatible charger that would draw less currrent + fit my laptop round charging hole, they gave me the same model number of the charger I currently have.

2

Are the AC ports on the planes actually turned on? I only ask from experience here in Oz where often on domestic flights the AC power outlets would not be activated for the flight. At least a few years ago.

3

I’ve had this issue before and found that the laptop would charge on the plane when it was turned off b/c it drew less power. When turned on, it drew more power than the outlet would support, triggering the outlet to turn off for 5 min. Not sure that’s helpful for you, but maybe worth trying.

4

Yes, that was my first thought - I rang the help light both flights and they said it was working “if it is green” and it was green.

but reading more, it seems like the airlines cap it at 75w, which is pretty low! only 0.625 amps @ 120v

Apple claims it’s 95w chargers work even at 75w, but finding something so darn low, I don’t know if it will even charge it.

5

I tried that as well - powered down & zip, nada. Darn it. If I could have had an hour of charging, it would have made a lot of difference!

6

You’re going to want a power bank to charge from, most likely. The size needed will be based on the time you need to extend your laptop charge. So if you’re gaming and you get an hour but the flight is for 3 hours, you’re going to want a pretty beefy power bank. Though I don’t think they will list your ASUS laptop for reference, some list Macbook Pros and Steam Decks in relative charge numbers, so you can get a guess for your laptop. Ex. if it’ll charge a MBP 1.5 times, that may mean the same for your laptop. They are a bit heavy not not overly huge. I usually put mine in the seat storage in front of me.

These are what I’m talking about …

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7

Yeah, I concur that a power bank would make more sense than buying a lower-watt charger.

This one gets recommended frequently:
https://www.amazon.com/Anker-Portable-Charger-PowerCore-Microsoft/dp/B0B9XHR6BG

I caught this one on a $30 sale a couple of weeks ago and it seems fine so far:
https://www.amazon.com/dp/B08VDJP7WN

8

Just be aware: current guidance for air travel is that you cannot bring a battery pack with more than 100Wh of energy without prior authorization by the airlines. Spare battery packs of any kind are not allowed in checked baggage. That AOHI, for instance, is over the 100Wh limit.

I believe that mAh capacity ratings are at the nominal output voltage of the lithium cell, which is 3.7V, so anything under about 27,000mAh is ok.

9

Good to know, mine isn’t over that limit but then again it’s never in checked baggage, only carry on and I’ve never had anyone dig it out of my bag to even check. Did you run across this due to it being posted somewhere close, Matt or was someone refused to use one?

10

I’ve had my large batteries scrutinized on international flights, so I looked up the regulations.

11

Mine is currently 20,000mAh, it’s kind of small looking though. We have a very large unit for camping that I’m SURE wouldn’t pass regulation if that’s the case, but then again, why would I even lug that thing around. It’s for charging multiple devices while camping for days.

EDIT: Actually it looks like I’m at the -checked bag- limit, so at USB rated 5V, it’s 20,000mAh. And it’s based on the amount of lithium per battery. I wonder where that leaves new battery technology once we get there (if ever?)

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However if you carry on, the limit would fall like so:

Lithium batteries with more than 100 watt hours

  • Carry On Bags: Yes (Special Instructions)
  • Checked Bags: No

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). This size covers the larger after-market extended-life laptop computer batteries and some larger batteries used in professional audio/visual equipment. There is a limit of two spare batteries per person for the larger lithium ion batteries described above (101–160 watt hours per battery. For more information, see the FAA regulations on batteries.

This instruction covers spare lithium metal and spare rechargeable lithium ion batteries for personal electronics such as cameras, cell phones, laptop computers, tablets, watches, calculators, etc. This instruction also includes external battery chargers (portable rechargers and power banks) containing a lithium ion battery. For lithium batteries that are installed in a device (laptop, cell phone, camera, etc.), see FAA regulations for “portable electronic devices, containing batteries.”

So the equation there to know would be 2x 32000 mAh external power bricks at 5v output could be carried on.

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12

This is an important caveat.

13

Very good point. but that also means the noted benefit that the 20000 mAh batteries don’t even require approval. Surely they created a loophole here. I could bring a bag full or 20000 mAh batteries onboard with me without pause but no sir, not larger than that without approval.

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Just pointing this out because I have to review technical documentation sometimes and it’s the little things that get missed.

14

You fool! Keep the secret of perpetual energy hush!

15

“Okay, you ten people around me, everyone plug in the cable now, lets get this chain going…”

How are we ever going to reach 1.21 gigawatts?

16

I bought a 65 W power brake just for airplane fights. It does provide some charge. My laptop fusses and says to use the appropriate charger to have it charge fully but I hope that if I’m not doing anything to this will be enough to last for much of our trip to Japan next month. Will report back whether it worked :-)

17

@Tman, the other thing to do is create a power config for that ROG Strix to minimize power usage, assuming you don’t need gaming/compiling/etc. performance when flying.

I had a ROG Zephyrus M16 before I switched to a MacBook Air 15**, and I had a few power profiles set up on it. One for gaming on the 4K TV (and simulating the sound of a shop vac), one for normal usage, and one for browsing/writing where I wanted maximum battery life.

The browsing profile was set to reduce the screen refresh rate to 60Hz, lower brightness, CPU performance (enable “silent mode”), turn off keyboard lighting, etc. to maximize battery life. It took the M16 from about two hours of battery life to nearly four. That’s one advantage for your scenario, but the other aspect was that it reduced the power usage of the laptop, allowing it to recharge under use with less power. With the low-power profile set, I could actually charge off a 65W USB C charger while using it instead of having to carry the power brick.

** MacBook Air 15’s 14-15 hour battery life has made Windows a “gaming desktop and ROG Ally only” OS for me now.

18

Thanks. That’s super helpful. I haven’t made or even knew I could create a power config and more importantly, I only thought the ROG Strix could be charged with AC. I was confused on the earlier things to use a power brick when there is no AC plug-in, but I looked at the back of mine and it appears there is a USB-C charging port as well. I’m going to need to try that.

19

The 65w power supply worked well, laptop got down to 35% by end of the flight,

20

My last work laptop was an engineering model. It took a whopping 165W power supply. Back when I got it, you could rarely find anything to charge it locally, you’d need to order a power supply if you forgot yours.

I’ve been known to be forgetful, but for some reason I just had a really bad string of forgetting to bring the power supply for that thing on multiple business trips. I did leverage the use of smaller power supplies that wouldn’t charge it, but would slow down the drain on it as I used it, but by the end of the lease on that thing I was done with it and went with a smaller and more efficient laptop.