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The Anker Astro E& battery is the best overall choice because it has the largest charging capacity while still maintaining a convenient size and weight. The packaging is roughly the same size as a standard smartphone, so it's portable, but has a huge 26800-mAh capacity, which is enough to charge an iPhone seven times. It has three USB outputs and a lightening fast 4-amp total output, which ensures that your devices charge up as fast as possible (note: each single port maxes at 3 amps).
One of the best features of the Anker battery is the PowerIQ, which keeps your technology charging as efficiently as possible, with no chance of a short circuit across devices. Whether your device runs Apple, Windows or Android, the PowerIQ port will detect and adapt the amperage to the most effective setting, eliminating frustrating slowdowns while charging. In addition to the output current stabilizer, it offers automatic shut-off sleep mode, power overload recover and battery cell protection.
It’s compatible with most USB-charged devices, including Apple's iPhone, iPad, Google Nexus 7 and many other brands. Anker also includes an 18-month warranty, and they will replace the battery if you encounter any problems. The simplistic yet beautiful case design weighs 15.8 ounces, is very durable and comes in either black or white.
About the same size as a cell phone (although much thicker), the Giant+ Power Bank easily fits into your pocketbook or backpack. A 12,000-mAh charging capacity makes it great for several full charging cycles on your devices, and 3.4-amp output makes sure they get to full capacity quickly. While it may only have two output ports, it could be perfect for charging both your phone and iPad without noticing any slow down between the two charging at once. The charger comes with an 18-month product guarantee, and it also covers the device if it conks out at less than 500 charge cycles.
A USB battery suited to nearly anyone's needs, RAVPower's adapter provides 16,750 mAh of power in a handy 5” x 3”, 11-ounce piece of technology. With a max output of 4.5 amps over two output ports, this is a great battery for the average consumer. It has super-fast charge speeds, and enough capacity to hold several full charges worth of power. It is an excellent compromise between speed, capacity and size.
RAVPower comes equipped with iSmart technology and automatically detects the amperage of your device and gives the appropriate volts, reducing chances of a short circuit or any power being wasted in the charging process.
RAVPower also prides itself on durability, with this battery easily lasting through 500 or more charging cycles. A stylish look also adds to the overall quality, and LED lights keep the user informed of the remaining power capacity.
The Anker PowerCore+ mini is a must-have on your keychain and might be the most genuinely helpful of every USB battery listed here simply because of its miniscule size. This battery is about the same size as a tube of lipstick, which means you could easily store it in any size bag/purse. The PowerCore+ mini has a 3,350 mAh capacity, which should get you roughly one charge on an Apple iPhone 7, Samsung Galaxy S7 and similar size smartphone. Also keep in mind that with a 1.0-amp charging system, this charges a little slower than some of the other listed options. But the size more than makes up for that.
With a 26,000-mAh capacity, an output of 4.8A amps and four USB ports, this is the only device you need for all your charging needs. Charging several devices at once will result in a slower charge time for each, but the convenience may be well worth it, and is a necessity on family road trips where everyone has a power-hungry device. It also has two micro-USB inputs on the side that can also be utilized to speed up charging time for one or two devices.
Available in black/orange or black/grey, the Monster comes with a built-in LED flashlight, as well as LED lights that display the remaining power in the bank. But perhaps most important in the features list are the safety ones: Internal technology ensures there will be no unexpected damage to your devices, either from a potential short circuit or problems with the power supplied.
If you need to charge many devices, or want one battery you can rely on for up to a dozen charges, the EasyAcc Monster is hands-down the choice for you. This battery is well worth the money, thanks to its efficient and tandem charging features that are unavailable on many other USB batteries on the market.
If you need serious capacity for your portable USB battery, RAVPower’s 26,800 mAh model is another worthy option. This model has so much power that you could charge an Apple iPhone 7 nine times or an iPhone 7 Plus or Samsung Galaxy S6 six times before having to re-charge the RAVPower. And with its 5.5-amp charging system, this means your devices will charge up twice as fast as plugging your smartphone into the wall at home. For example, it can charge an iPhone 7 from empty to full battery in less than an hour.
This model weighs one pound and measures 7.5 x 5.6 x 1 inches, so it’s not the smallest brick, but it can’t be because of how much battery is on board. The design of this model stands out for being somewhat sleek, too, as it offers a classic black matte case that is scratch resistant. Three USB ports that can be used simultaneously, and a blue LED light indicator on the side that shows you how much juice is left.
Courtesy of Apple
With the previous Powerstation models establishing this company as an industry leader, the Mophie Powerstation Plus is an Apple-exlusive product and a true workhouse, delivering hours of power to everything from your smartphone to your tablet. The built-in switch-tip cable charges a variety of compatible Apple and micro USB devices, negating the need for the hassle of multiple cables and providing the fastest charging speed possible thanks to 2.1A output and smart adaptive technology. Smart technology is also integrated into the charging circuitry to ensure that your device receives the right amount of power.
To check the charging status and the Powerstation's current battery levels, press the integrated power indicator button to make sure you’re never caught off guard by a drained device. Built with a sleek, low-profile design and a premium fabric finish available in multiple colors, the 6,000mAh battery offers up to 20 extra hours of power for an iPhone X.