Originally Posted by
StuckInYYZ
Just wanted to add some commentary...
As for power banks... 2-3 8-10k mAH power banks are more effective than a single 20+k mAH power bank. Power banks in general charge VERY slowly. There are some fast charging ones out there, but they tend to cost more. Depending on how much you drain from them, they can take more than 8-12 hours to charge up (and this is at 10k...at 20k, good luck) You could easily end up with a partially drained power bank moving around. I use 2-3 of the 10k power banks (depending on situation) when I travel. Sure during transit it weighs a bit more, but then I can often leave one charging at all times during travel so I have a fully charged one with me at all times.
That largely depends on the quality of the power bank and the quality/size of the charger you're using. My Anker 20k mAh pack charges fully in around 8 hours, my Anker 6.7k mAh pocket charger will charge fully in about 4ish. Though I now need to go and verify that, but in general, my 20K is good to charge my ipad and iphone BOTH at least 1 to 1.5 times on a long-haul where I'm in the air for upwards of 20 hours (spread over multiple legs, the longest being the typical 14h US -> Asia leg).
That said, I've had smaller, much cheaper packs (2000 mAh range) take upwares of 4 hours as well. Quality of the components makes a real big difference, as does using a 2.4 or 3.1 Amp rated charger as opposed to a 1.1A cheap charger. I've not measured it, I never take my little USB meter with me, but I have a suspicion that on most aircraft, the USB port, IF it provides power at all, doesn't provide enough charge to speed charge anything, only enough to offset usage).
For me, the loadout tends to look a bit like this:
20k mAh pack fully charged
6.7k mAh pack fully charged
1x micro usb and lightning cable rated for high current
1x 2 port 3.1A USB charger
1x plug adapter for which ever countries I'll be transiting through and arriving in.
if I have a long layover, I'll recharge in a lounge or in the terminal using AC or a USB charging station and save the batteries for in-flight where necessary. And I've yet to find a trip where I ever needed to dig into the 6.7K pack because between seat power (even with loose/flaky outlets) and charging during layovers I've never had a device go dark, and my phone is always at least 75% charged by the time I reach my destination. YMMV with usage though, I don't use BT or Wifi onboard which both will add to drain, I watch downloaded Netflix movies on my iPad and use a Bose QC-20i headset (the battery on that for ANR will last me up to 16 hours on a single charge) directly connected.