Last updated: 8/3/2016
Our Anker Astro E7 battery pack rating:
Anker Astro E7 battery pack at a glance

The Anker E7 battery pack charges all the things, with plenty of power left to spare! Shown here with an LG G4, iPhone 6, and iPhone 4S for size comparison.
Powerful and portable, this just-a-bit-bigger-than-pocket-size battery pack recharges your phone, tablet, camera, several times over. Typical use sees up to 10 full recharges for an iPhone 6 and 2 full recharges for an iPad Air.
Super useful!
I didn’t realize how many uses I had for a portable Anker battery pack until I saw it in action.
- Car trips – especially in cars that have just one (or zero) USB ports
- Charges via USB: (alas, you cannot plug it into itself to charge it indefinitely)
- Away from home – small and light enough to bring to school or work in your backpack
- Airports and airplanes – I’m looking at you, Chicago O’Hare and your painful lack of terminal outlets (and you, old airplanes, and your lack of on-board outlets)
- Holds a charge for a long time– take it camping!
- 3 USB ports so you can charge multiple devices simultaneously
- Charges devices as fast as a wall charger – modern smartphones charge at a rate of about 1% per minute
We’ve had our Anker for nearly a year now and it still gets a ton of use any time we travel or stalk Pokemon in the local park.
» Check current Anker E7 Astro price on Amazon.com «
Pros
- 26,800 mAh capacity is enough, depending on your device, to charge it up to 10 times (for comparison, the iPhone 6 has a 1,810mAh battery)
- PowerIQ technology discovers and replicates each device’s charging protocols, for extra reassurance that it won’t render your phone into a slag heap
- Won’t overcharge your device: it stops when your device reaches 100%
- 3 USB ports for simultaneous device charging
- Max charging speed: 4 amps, but it adapts to your device’s limitations
- Safety features: auto shutoff sleep mode, output voltage surge protection, output current stabilizer, low voltage protection, and short circuit prevention
- Anker is a reputable brand: Over 10 million units sold in North America (fun fact: 1 in 3 chargers sold on Amazon.com is an Anker)
- The FAA allows it onboard: long flights just got a bit more tolerable
Cons
- It’s another thing to remember to bring along, and it only works if you remembered to charge it in advance.
- No wall charger included!! (Anker’s PowerPort 4 40W charger has you covered – charge your battery pack and your devices from a wall outlet with this one cool charger. There’s also an Astro with an included wall charger, but I think you can get a better wall adapter by buying separately.)
- It takes 11-12 hours to charge the battery pack to full
- A bit heavy at just over 1 lb (453 grams)
- You can’t use it while it’s charging
- It’s a fingerprint magnet that may inspire you to constantly buff it back to perfection
Anker E7 Astro battery pack review
What’s in the box?
- The Anker battery unit itself
- USB to Micro USB charging cable (about 12″ long)
- Instruction booklet
- Cinch-bag to protect the battery from scratches
- 18 month warranty card
Sturdy and stylish physical design
It’s sleek and small, but it’s got a fair bit of heft to it (the Anker pack weighs about a pound). I wouldn’t carry it in a purse, but it’d be unnoticeable in a backpack or carry-on luggage. Alas, its shiny black case will be a mottled canvas of fingerprints by the time you’re done fondling it for the first time.
The 4 on-unit LEDs indicate how much power remains in the battery pack and their meaning is pretty straightforward:
- Four LEDs lit means fully charged
- Three LEDs lit means 75% battery remains
- Two LEDs lit means 50-75% battery remains
- One LED blinking means less than 25% battery remains
It even has a flashlight! There’s a button on the side that turns the flashlight on and off (hold it for a full second). This is a nice touch if you’re one of those people who is prone to turning the lights off first and then struggling to jam the plug into the USB port up, down, up, down…
Which brings me to one final point about the Anker’s USB ports: they’re really stiff. You gotta push to get your USB cables plugged into this thing. Once I got used to it, I decided I liked it. The Anker plays for keeps with your USB cables, so there’s less chance of them falling or getting pulled out of the charger.
Smart charging features
The Astro E7 features a fully automated power on/off system. The Anker’s battery turns on when a USB plug is connected, and turns back off automatically when the last USB plug is removed (so you don’t have to manage it).
The IQ ports determine the maximum appropriate charging speed for a connected device and deliver charge at a safe speed for that device.
3 USB ports and the oomph to power them
Most battery packs just don’t have the capacity for charging multiple devices at once, but the Astro E7 has more than enough power to go around. As a group, the USB ports are capped at 4 Amps of total power output. A power-hungry device like the iPad charges at 2.1 Amps, but that leaves enough Amps left over to plug in another couple of phones and get full-speed charging for all three devices simultaneously.
(As an aside, this is an interesting article on why iPad charge time varies so much by charge method.)
Charging speed: just as fast as the wall outlet
Charging my iPhone 6S and my friend’s LG G4 went at about a rate of 1% and .08% per minute, respectively, which is about the same we get when charging from our wall chargers. In both cases, our phones were doing other things, like browsing the web (the iPhone 6 test) and streaming Spotify (the LG G4 test).
Crazy capacity
You might’ve noticed the battery pack has a 26,800 mAh capacity and the example device, the iPhone 6, has a 1,810mAh battery. So why does Anker say you only get 10 charges instead of 14.8 charges? That’s because, as with any battery pack, about 30% of the battery power is expended in heat and voltage conversion and powering the device itself.
(Pro tip: to charge your phone faster, put it in Airplane mode so it doesn’t sit there receiving emails and push notifications while you’re trying to fill it up.)
Still, 26,800mAh is a friggin’ beast of a battery. For comparison, here are some common devices and their own battery capacities:
- iPhone 6S 2,750 mAh
- iPad mini 4 5,124mAh
- iPad Air 2 7,340mAh
- iPad Pro 10,239mAh
- Samsung Galaxy 6S 2,550mAh
- LG G4 3,000 mAh
- Kindle Fire HD 4,400mAh
Pro tip: Get a case
If you love your Anker as much as we love ours, you’ll be taking it lots of places. The Anker’s shiny body is prone to scratches and fingerprints, so we recommend getting a case for it. This hard-body travel case by Khanka is both cheap and great.
The bottom line
Anker set the new standard for portable battery charger packs with the Astro E7. They’ll undoubtedly raise the bar again in the future, but for now, this is the battery pack to buy. Astro E7 is missing only a single thing: a wall power adapter like this one. (You can also buy the Anker E7 with a battery pack included.) With an unbeatable battery size and the ability to charge up to 3 devices at once (and most or all of them at their fastest-possible charge speed), Anker Astro E7 is the current best choice in portable battery packs.