Anyone who uses a smartphone knows the importance of carrying a
backup battery pack. But try searching for one on Amazon, say, and
you're likely to feel overwhelmed by the vast number of options.
Besides the various charging specs, ports, and even cables you have
to consider, there are a ton of competing brands. How are you
supposed to know which ones actually live up to their promise?
We've done the legwork for you, evaluating a wide range of power
banks from different manufacturers, costing different prices, and
some offering unique features. Our testing is extensive, too,
subjecting the packs to real-world usage (read about our testing process in detail below). Our picks
below reflect a range of needs. (You might also be interested in
our our roundup of USB car chargers if you spend a lot
of time in transit.)
Updated 10/22/2021 to include our reviews
of the Goal Zero Yeti 1000X, a pricey portable power
source that earns its keep with sufficient backup power to run
appliances, and expansion options that could help the 1000X power
an entire house in an emergency. Scroll to the bottom of this
article for links to all of our power bank reviews.
Best overall power bank
Building on the success of the Powerstation Plus XL (our
previous pick for best overall power bank), Mophie's Powerstation
XXL matches its predecessor in efficiency, achieving 92.51 percent
of its stated maximum current, plus it's stylish, portable, and
affordable price. It's a no-brainer recommendation if you're in the
market for a dependable power source on-the-go.
Best budget power bank
The combination wall charger and portable power bank format
makes the Powercore Fusion 5000 exceedingly convenient. The bank
itself can be recharged via either method—power outlet or MicroUSB
port. It's limited to two USB-A ports for device charging, but that
doesn't dimish its great handiness-to-cost ratio.
Most portable power bank
Small enough to fit into a coat pocket or the side pocket on a
backpack, the Tronsmart Presto is an obvious companion when you're
on-the-go. It's a 10,000mAh (37Wh) pack, with two USB-A ports, one
with QC3.0 for fast charging.
Best power bank for road
If you spend a lot of time on the road and value device
preparedness, the Sherpa 100AC makes a trusty, if pricey,
companion. Yes, at $299.95, you're looking at a big investment. But
that buys you two USB-C ports capable of fast-charging speeds, two
standard USB ports, a Qi wireless charging pad, a standard U.S.
110V outlet, a full complement of cables, and a nifty status
display and buttons for controlling various functions of the pack.
The pack itself can be charged in just a couple hours.
Best USB-C power
bank with Power Delivery
Sporting the sort of sleek yet rugged exterior you'd expect from
Otterbox, the Fast Charge 20,000mAh is both handsome and
utilitarian. Its USB-C port with Power Delivery can be used to
charge other devices or the pack itself. Both it and the USB-A port
are capable of 18W output. The pack's 92.55 percent efficiency is
among the best of the USB-C battery packs we've tested.
Best portable power
There are times when a mere power bank isn't enough—the
circumstances call for a power station. Say you're
spending the weekend off the grid. Or you want to be prepared for a
future emergency. The RAVPower Portable Power Station 252.7Wh Power
House will get the job done. With a capacity near 252.7Wh, a nice
complement of ports, a built-in flashlight, and an included
carrying case, this highly portable power station makes a great
travel companion for road trips.
How we test
Determining whether a power bank lives up to a company's promise
entails more than simply connecting it to a phone and charging.
Testing battery packs is done over weeks, not days, and requires
extra equipment in order to ensure the batteries work as
1. Upon receiving each battery pack, it's fully charged, using
indicator lights as a means to track charge level.
2. Then to track efficiency, we use an AVHzY USB Power Meter in tandem with a DROK Micro Load Tester.
As we use the DROK load tester to drain the pack of power, we
are able to test against a battery's stated maximum current, and
verify that proper shutdown mechanisms are in place should
something go wrong during a charging session (such as a device
drawing over the maximum amps).
By using the AVHzY USB Power Meter, we are able to monitor volts
and amps, total power throughput, and total amount of time to
deplete a battery from full to empty. The meter can create an Excel
spreadsheet of the entire process for future reference.
3. Next, we recharged the battery, this time using the AVHzY to
track it and chart the amount of time it takes to reach full
The AVHzY meter solves a shortcoming we had with our previous
method with the PortaPow. Previously we had to use a GoPro camera
to track each battery through its charge cycle, as the PortaPow
monitor would continue to collect data after the battery was fully
charged (trickle charging is normal, and unfortunately interferes
with our testing).
If a battery was capable of charging through USB-C, we use that
instead of Micro-USB.
4. The AVHzY also has a feature built in that checks a charging
port for all of its supported charging standards. We are able to
run that test and get an instant readout to confirm support for QC
3.0, for example, without needing to have compatible phones or
devices on hand.
Power source and cables
All of our tests were conducted using the same wall adapter and,
when possible, USB-C or Micro-USB cable. This was done to eliminate
any discrepancies with wall adapters and cable throughput.
What to look for
in a portable power bank
Without fancy testing equipment, you never truly know if you're
getting what you paid for with a battery pack. Vendors, especially
in Amazon listings, like to throw around a lot of terms and
Here are a few tips to help you make a decision:
- For those with a compatible device, make sure the battery pack
is Quick Charge 2.0, 3.0, or PD certified. Depending on your
smartphone, this can make a big difference in performance. If you
own a QC 2.0 device, however, ask yourself if paying extra for a QC
3.0 capable pack is worth it.
- Don't put 100 percent confidence in a company's claims of a
pack being able to charge, say, a Galaxy S8 or iPhone X six times
over. Battery capacity and efficiency varies based on a number of
factors. Read this Macworld report on USB-C packs to learn more
about batteries and capacity.
- Look at the specs of the battery, and ensure that its input
isn't limited to slow charging such as 5V/1A. The faster the input,
the faster your battery pack rechargers, the faster you're ready to
hit the road.
All of our power bank
Click on the links below to read the full reviews of all the
products we tested for this roundup. We will continue to review and
update this article as we test more battery packs.
You may also be considering simply buying Amazon's AmazonBasic
charger, as a way of saving money. In this case, be advised: Amazon
has voluntarily recalled several models because of potential
overheating. Amazon has received 53 reports of the affected models—B
00LRK8EVO, B00LRK8HJ8, B00LRK8I7O, B00LRK8IV0, B00LRK8JDC or
B00ZQ4JQAA—overheating, and in one case causing chemical burns. You
can find more information at the Consumer Products
Safety Commission, as well as Amazon's own recall site.
Otterbox Fast Charge 20,000mAh
Read our full Otterbox Fast Charge 20,000mAh review
Read our full Presto PBT10 review