UPDATE: Just as a temporary (Fall 2018) note for those interested (I think this is going on for another month) but Omnicharge has a new device, the Omni Ultimate, that looks pretty great and is only $50 more than their Omni 20 device on pre-order ATM with significantly beefed up specs. My only reservation about recommending for everyone is that it has a 145Wh battery that puts it in the may require approval category and it’s a bit overkill, but it has the highest DC output voltage (150W) and that is adjustable from 5-60V in 0.1V increments (!), which makes it an amazing option if you have a lot of devices (drones, cameras, laptops, etc) that you are carrying around.
I got sidetracked into looking at some of the latest big power bank options (something I last did a year or two ago) and there’s been a few interesting updates. There are a lot more “stick” form-factor inverters like the Jackery PowerBar, although personally I’d much rather have 12V and 19V DC output.
If you’re looking for the cheapest, most compact, highest power output, flight-allowable (100Wh max) battery, it actually remains the same – the RAVPower 23000mAh or the Poweradd Pilot Pro2 (basically the same design). This is pretty no-frills/basic, but has impressive energy density and gets the job done, with 12V and 19V output and decent amperage.
If you need an inverter or are price insensitive, the Omnicharge Omni 20 is pricey, but is very well designed. It also has extremely wide input (4.5-36V) and output (1-24V) options, and the output is selectable to 0.1V – that means you can for example, charge a Mavic Pro battery directly w/o an additional adapter, as it wants 13V+ to charge. It will also take an input of 45W, tied for the fastest charging of anything I’ve run across. It’s surprisingly the same volume as the RAVPower battery, although a bit heavier and less energy dense. There’s also a new USB-C version, and while I don’t care about the lack of inverter, it’s also missing the variable DC output entirely, so not for me, but it’s lighter and cheaper, so maybe worth considering if you’re all USB-C PD.
The Goal Zero Sherpa 100 has come down a bit in price a bit and is also a great option. It has a detachable inverter, is chainable, and most importantly, has the highest power output (120W max – 10A @ 12V and 6A @ 19V) and the fastest recharge time of anything I came across. While I haven’t used the Sherpa personally, I’ve had good past experience w/ many types of Goal Zero products in some pretty torturous production conditions.
I’ve included my spreadsheet below, I got a bit pooped out after a while since there are so many clones/bad options available. There are a few decent options that are way too big to fly with. Oh, for fun, I do have a sheet specced out if you know what you’re doing and thinking about building your own pack and wanted to build something more compact that can output 200W. Oh, the Wirecutter is only mildly wrong this time, but mostly because they assume that you want to recharge your laptop or other DC devices and suffer inverter power loss in the first place.