We considered 18 USB-C battery packs and tested seven contenders over dozens of hours, and the Tronsmart Presto 10400mAh Type-C Battery Pack is the best power bank to charge USB-C–equipped smartphones and tablets on the go. The larger Anker PowerCore+ 26800 PD Battery Pack and Charger Bundle, which provides twice as much power, is our pick for keeping a USB-C–powered laptop charged. However, if your devices don’t have USB-C ports—that group includes many Android devices, and all iPhones and iPads—and you don’t plan to buy the latest and greatest Android smartphone in the next few months, our guide to standard USB battery packs offers more variety at lower prices. We also have a guide to portable AC power banks if your laptop isn’t USB-C powered, or if it needs more power than the current generation of USB-C batteries can provide.
The Tronsmart Presto 10400mAh Type-C Battery Pack offers enough capacity to charge most smartphones three times, but it’s small enough and light enough to sit in a computer bag, backpack, or purse. You can use the USB-C port to charge your device or to recharge the pack itself, leaving the USB-A port open to charge devices that don’t use USB-C. The Presto 10400mAh is the only currently available USB-C battery that is light enough to carry every day, equipped with a fast USB-C port in and out, and sold at a reasonable price.
Few USB-C Power Delivery–capable batteries are available right now, and they’re limited to charging speeds best suited for laptops 13 inches or smaller—larger computers will charge much more slowly. Still, if you want to charge a USB-C–powered laptop such as a MacBook or a Lenovo ThinkPad X1, look to the Anker PowerCore+ 26800 PD Battery Pack and Charger Bundle, which will give you the capacity, charging speed, and reliability to keep working or playing on your laptop for at least one whole charge when you’re away from a wall outlet.
Table of contents
- What size should you get?
- Why you should trust us
- How we picked and tested
- Our pick for mobile devices: Tronsmart Presto 10400mAh
- A more powerful, laptop-ready pick: Anker PowerCore+ 26800 PD
- What to look forward to
- Flying with batteries
- The competition
What size should you get?
If you have a USB-C–powered laptop and want to charge it without hunting for a power outlet, you should choose our bigger laptop-ready battery pick. If you’re just looking to power your USB-C smartphone or tablet, you can save some money by getting our smaller, lighter, mobile-device pick instead. Here are the defining characteristics of what we call mobile battery packs and laptop-ready battery packs:
USB-C battery characteristics
Mobile-device battery packs
Laptop battery packs
|Top charging speed||15 W||30 W +|
|Charging standard||USB Type-C||USB Type-C Power Delivery (PD)|
|Capacity||Up to 15,000 mAh / 50 Wh||More than 15,000 mAh / 50 Wh|
|Size||Fits in a backpack, purse, or large pocket||Fits in computer bags and luggage|
|Laptop charging||Might slow-charge smaller, low-powered models||Works with many USB-C PD–powered laptops|
USB Type-C—or more simply, USB-C—is really just the name of the port. Type-C ports can come in three basic power flavors, with more-powerful ports backward-compatible with the less-powerful flavors:
- Legacy charging: up to 12 watts (2.4 amps / 5 volts), the same as traditional USB-A
- Standard USB-C: up to 15 W (3 A / 5 V), the common maximum for USB-C mobile devices
- USB-C Power Delivery: At least 30 W (2 A / 15 V or 1.5 A / 20 V), the minimum for larger devices such as laptops, but up to 100 W
You have no reason to buy USB-C charging gear that works only at legacy charging speeds, and manufacturers have no reason to keep making such models (other than savings on development costs). So we did not consider any of those slower packs.
This guide focuses on the other two flavors: Standard USB-C charging is typical for most mobile devices. It offers roughly 25 percent faster charging than most USB-A chargers have used in recent years. Power Delivery (PD) charging, on the other hand, jumps to three times the common output of standard USB chargers and works with newer USB-C–equipped laptops.
Starting at 30 watts—or twice as fast as what standard USB-C chargers offer—PD chargers and devices can be designed to use up to 100 W. Laptops need anywhere from 30 W to almost 90 W of power, depending on the model. The first generation of USB-C PD battery packs can charge 30 W laptops, such as the 12-inch MacBook, at full speed, but can charge most larger models at a speed slower than a traditional laptop wall charger. For example, the Dell XPS 13 comes with a 45 W wall charger, while the 2016/2017 13-inch MacBook Pro charger is 61 W. You could use our top mobile-device pick with either computer and still extend its useful battery life, but if your laptop is about to run out of juice, a 30 W PD power bank may not charge fast enough to compensate for high-power draws like gaming or video editing. (Imagine that your computer’s battery is a water barrel—using a slower charger is like having water drain out of the barrel faster than you can fill it up.) As we test more batteries and more laptops, we’ll update the compatibilities and test results in this guide.
Why you should trust us
I’ve been covering batteries and electrical devices for The Wirecutter for two years, and in that time we’ve cataloged and considered nearly 300 different USB battery packs. And that’s on top of the dozens of hours of work we’ve put into prior versions of our coverage. That coverage includes working with the battery testing and fabrication experts at Cadex, and having our testing highlighted on Good Morning America.
In our efforts to gauge battery packs’ failure rates and long-term reliability, we regularly comb through customer reviews, though always with a skeptical eye. Because some disreputable companies sell items that don’t adhere to the USB-C standards, we’re careful to try our recommended battery packs in a variety of situations with an assortment of cables and devices. Although Benson Leung and Nathan K.—independent engineers who have been testing USB-C product compliance—have yet to publish tests of our picks, we reviewed their other work while researching this guide. We also worked with our own consulting engineer, Lee Johnson, to test the non–USB-C functionality of our batteries.
How we picked and tested
We’re constantly on the lookout for new USB-C–capable battery packs, scanning major retailers such as Amazon and Best Buy and staying on top of technology news. For this initial version of this guide, we researched, tested, and picked from the first wave of USB-C battery packs available in early 2017. We considered the price, the charging speed to devices, the recharging speed of the pack itself, the capacity, the usability and design features, and the warranties and included accessories. Though we weren’t able to analyze the USB-C protocol and USB-C compliance for this guide, we did test each battery with a variety of devices to make sure each one was up to snuff.
Charging speed or power output: Your computer or smartphone should be able to charge from the battery as fast as possible, and not be held back by a slow battery pack. Even if you have older, slower-charging devices, a battery that can charge gear quickly will be more flexible in the long term. (Less power-hungry devices, such as MP3 players or rechargeable flashlights, will still charge safely, as they take only what they need.) The standard USB-C power output—15 watts—is good for smartphones and most tablets, so we considered standard USB-C models for our mobile-device battery picks. We considered batteries with USB-C PD ports—those models that could put out 30 W or more—as laptop-ready batteries because they were capable of charging many USB-C–powered laptops. (Some laptops can charge slowly from some battery packs that we’d consider only for mobile devices—that’s fine in a pinch, but we don’t recommend it.)
To test each power bank, we started with a full battery pack and plugged in a simulated device in need of charging. (Our “simulated device” consisted of an assortment of USB-capable programmable load testers.) To test the maximum current output, we slowly turned up the load of our simulated device and recorded the output when either the battery shut down or the voltage dropped below the acceptable level. (According to the USB standard, ports operating at 5 V can vary +/- 5 percent.) We repeated the same test for each output port—both USB-C ports and any USB-A ports—to confirm whether each one charged mobile devices as fast as possible.
Common laptop power levels over USB-C
Laptop make and model
Wattage of USB-C power supply
|Apple 12-inch MacBook||30 W|
|Dell XPS 13||45 W|
|Apple 13-inch MacBook Pro with Touchbar||60 W|
|Lenovo ThinkPad X1 Carbon||65 W|
|Apple 15-inch MacBook Pro with Touchbar||87 W|
If a battery had PD-capable ports, we also tested it with a USB-C laptop. For this edition of this guide, we used a 13-inch MacBook Pro with Touchbar, because its charging requirements rank in the middle of the pack at this writing. We drained the laptop’s own battery to less than 10 percent to ensure that the laptop would draw as much power as possible, after which we plugged the laptop into each test battery and monitored the power using an inline power meter. Even though the USB-C PD batteries available right now will charge many laptops more slowly than whatever wall charger came with the machine, good power banks should still provide a charge, and great ones consistently put out their maximum stated current, without fluctuations.
After charging our laptop, we also plugged each battery and its included cable into other devices to make sure the power level dropped appropriately and didn’t get stuck overcharging phones or other accessories.
Recharging speed or power input: How fast a battery charges a device is our top concern, but how fast it recharges itself is almost as important—large batteries can take a long time to charge, and there will come a day when you realize you haven’t charged your power bank and need to fill it up as fast as possible. A good USB-C battery pack uses Type-C ports for both input and output. Some cheaper models still rely on Micro-USB inputs to recharge the pack, but those previous-generation ports are about 25 percent slower than standard USB-C charging, so we dismissed those models without testing. Similarly, bigger packs need to use the faster PD speeds. For huge batteries, such as models made for charging a laptop, the difference that PD charging offers can be significant: A 92 Wh (25,000 mAh) battery that would take more than 10 hours to charge without PD can instead fill up in as few as four hours. (To take advantage of USB-C PD speeds when refilling the power bank, you must use a USB-C PD charger. Our top pick comes in a bundle with one.)
To test power input, we started with a fully drained battery pack, a high-speed USB-C charger, and an inline power meter. We started with the pack’s battery at zero, because these devices tend to pull the most power when they’re at their lowest charge; this arrangement allowed us to test the upper limit of the power input. Once we saw a consistent measurement, we recorded the result and moved on to the next test. Most good batteries charge as fast as they claim, within about 5 to 10 percent. Most also get a little warm while charging, but excessive heat—enough to make the unit uncomfortable to the touch—would be a warning sign that something is wrong with either the particular pack or the design.
Capacity: A good battery has around 90 percent of the stated capacity, and a great one has over 95 percent. But the differences are so minuscule, and there are so many variables that will affect the results you get at home—the temperature, how many times you’ve charged it, how much you last charged it and at what speed, for example—that you have no need to fret over a few percentage points here and there.
To make sure that our test group didn’t have any duds or any sort of design flaws, we tested each battery’s capacity three times and then averaged the results. Each time, we fully charged the battery as fast as it could go, and then we discharged it at a constant 5 W (1 A / 5 V) using the same simulated devices as in our power-output tests. That’s slower than most devices charge, but this approach ensured that we would get a consistent draw during the whole process: The faster you drain a battery, the less capacity it has for your device, and because phones and tablets slowly lower their power draw as they charge, testing with a phone or tablet would have made it impossible for us to reproduce the tests time and time again.
Even though raw-capacity numbers are rarely a deciding factor, we also used this test as the basis for other metrics. A good capacity per dollar demonstrated that a power bank offered a good overall value, regardless of its absolute price or capacity alone. Similarly, a higher capacity per cubic inch told us that a given pack would take up less space in your pocket, purse, or bag than another pack with a lower ratio but would offer similar capacity.
Design and features: Smaller battery packs tend to have just one output port, though great ones have two that can each charge devices at the highest possible speed simultaneously. For large packs, we’d like at least two USB-C output ports, but right now the more common offering is a single USB-C port along with one or two USB-A ports. That isn’t great, but it is good enough to be serviceable, and it allows you to use whatever cables you have on hand during this period of transition from USB-A to USB-C. Most battery gauges consist of just four small LED segments or dots, though we prefer batteries with 10 segments—they’re a hair more accurate, and they make it easier for you to know how much power you have to work with.
Warranty and extras: USB-C battery packs should come with a warranty of at least 12 months, and the warranty needs to be one that you can actually use—batteries can and do fail. The top brands, including Anker, Jackery, and RAVPower, have been around for a while and have a solid reputation in this regard. When we considered or tested a battery from a new brand, we also tested the customer service (via phone or email) to make sure that it was responsive and that the company would stand behind its products.
In general, we determine the best battery packs based on how they perform in our tests, not by what goodies come in the box. But sometimes those goodies are excellent tiebreakers. For this test group, as usual, when a battery pack shipped with exceptionally high-quality or extra-long cables, port adapters, or a wall charger, we factored those items into the overall value of the pack.
Our pick for mobile devices: Tronsmart Presto 10400mAh
The Tronsmart Presto 10400mAh Type-C Battery Pack is the best option for a USB-C–output battery that you can carry with you everywhere. Both of its ports—one USB-C and the other legacy USB-A—will charge your mobile devices as fast as possible. When it comes time to recharge the pack, the USB-C port serves as the input, as well, so the Presto 10400mAh recharges faster than packs with a Micro-USB input. The battery probably won’t be comfortable in your pocket, but it’s small enough and light enough for you to carry it in any computer bag, backpack, or purse, and it has enough power to charge most tablets more than once and most phones several times over.
Like all the best batteries, the Tronsmart Presto 10400mAh has one USB-C port and one USB-A port, and both will charge compatible devices as fast as those standards allow. That means USB-C devices will charge at up to 15 W, QC 3.0 devices will charge at up to 18 W, and standard USB devices will charge at up to 12 W. Despite the additional power that USB-C ports offer, some manufacturers are making packs (like this one from JTD) that put out only as much power as traditional USB. There’s no point paying extra for a battery with USB-C if it doesn’t take advantage of the extra power available.
The best USB-C battery packs also recharge themselves through their USB-C ports, and the Presto 10400mAh does so as fast as standard USB-C is capable—again, 15 W. Cheaper packs flooding Amazon advertise USB-C ports but still rely on Micro-USB input ports for recharging. That means you’d have to carry an extra cable for recharging and wait longer for that charge—Micro-USB ports are generally about 25 percent slower.
The Presto 10400mAh can charge most smartphones three times or most tablets once. This is a good capacity for most people, because it keeps the pack small and light enough for you to carry it every day. The only packs that compete with the Presto 10400mAh lack high-speed and USB-C recharging, or come from companies without obvious customer support. Because of that, the Presto 10400mAh’s size and capacity made it something of a pick by elimination. Though we wouldn’t have picked it if we had noted any problems with the power output or quality, this is the rare case where our top pick had no good competition.
In our tests the Presto 10400mAh delivered power as expected under the new USB-C guidelines, so any standards-compliant device should be safe when plugged into it. We charged a MacBook Pro, then a USB-C device, then a USB load tester set to zero current, all while using the USB-C–to–C cable included in Tronsmart’s packaging. Each time, the Presto 10400mAh delivered the same power, without variations in voltage or amperage, as brand-name wall chargers we knew to be reliable. Though we hope to do more in-depth tests (similar to Nathan K.’s tests) in the future, thanks to this procedure we felt comfortable using the Presto 10400mAh to charge any devices we had on hand.
If you were to put two decks of cards end to end, they’d be roughly the size of this Tronsmart battery pack. It’s about an inch shorter than the Anker PowerCore+ battery we picked for use with USB-C laptops. But the Anker is also twice the weight—a full pound versus the half-pound of the Tronsmart Presto 10400mAh. The Presto 10400mAh is a size and shape that’s unobtrusive in even a small bag but a bit too long to keep in most pockets. The USB-C–in/out port and the USB-A–out port are on the same end of the Presto 10400mAh, and you tap a small button set flush along the side to start charging your device or to light up the four-LED capacity gauge along the top.
To test Tronsmart’s customer-service response time, we anonymously emailed the company’s email-only support with a problem. A representative responded five hours later with some troubleshooting tips and instructions for how to initiate an exchange if we couldn’t resolve our problem. While phone support is always a plus, Tronsmart’s prompt and detailed email support left us feeling confident in our pick.
A more powerful, laptop-ready pick: Anker PowerCore+ 26800 PD
If you want to charge a USB-C–powered laptop away from a power outlet, the Anker PowerCore+ 26800 PD Battery Pack and Charger Bundle is the best way to do that. This battery pack can provide more power, for longer, than our smaller mobile-device pick, extending the battery life on USB-C laptops such as the most recent MacBook Pro models, the Dell XPS 13, and the Lenovo ThinkPad X1. The Power Delivery (PD) standard delivers twice as much power as standard USB-C outlets—at least 30 W instead of just 15 W—but twice the power comes at around four times the price at this writing, so it’s important to confirm that you need the benefits before you plunk down the cash. Non-PD devices such as smartphones, tablets, and speakers will still charge from this pack, but not any faster than they would from much less expensive standard USB battery packs.
A growing number of manufacturers have adopted USB-C ports, but the higher-powered PD standard has become common only in 2017. For now, we’ve found just two good options if you want a PD-capable USB battery pack from a reputable company: the Anker PowerCore+ 26800 PD Battery Pack and Charger Bundle and the RAVPower 26800 PD Portable Charger. The two packs are nearly identical in their main features, but we like the faster recharge speed of Anker’s included PD-capable wall charger, something that RAVPower didn’t offer at the time of this writing.
The Anker PowerCore+ 26800 PD has a maximum output of 30 W on its one USB-C port, and in our tests we were able to regularly charge our 2016 13-inch MacBook Pro at that level. (We saw similar performance from the RAVPower pack.) As with our mobile-device pick, we checked the PowerCore+ 26800 PD to confirm that it delivered power as expected under the new USB-C guidelines, and we found no problems. We again charged a MacBook Pro, then a USB-C device, and then a USB load tester set to zero current using the USB-C–to–C cable included with the Anker pack. Each time, the PowerCore+ 26800 PD delivered the same power levels, without variations in voltage or amperage, as brand-name wall chargers. Though we hope to do more in-depth tests (along these lines) in the future, we were able to test the PowerCore+ 26800 PD with some popular USB-C–powered laptops to confirm compatibility.
Will it charge?
|Apple 13-inch MacBook Pro||Yes||30 W (~15 V, 2 A)|
|Dell XPS 13||No||n/a|
|Asus Chromebook Flip||Yes||30 W (~15 V, 2 A)|
|HP Spectre x360||Yes||20 W (~20 V, 1 A)|
As for the legacy USB-A ports for charging smartphones or tablets on the PowerCore+ 26800 PD, the output is a bit more limited. Either port on the Anker can charge devices up to about 12 W each (2.4 A / 5 V), but the combined maximum output is only 15 W. That’s a small inconvenience only if you want to charge two large smartphones or tablets at the same time, and it won’t be an issue at all if you’re charging devices overnight. Plus, the 15 W limit exists only on the USB-A ports and doesn’t affect the Type-C output. The RAVPower pack does a little better with a combined limit of 17 W, but the 2 W difference on USB-A ports is pretty minor.
In our tests we found recharging speeds—putting power back into the battery pack—to be a bigger differentiator between the PowerCore+ 26800 PD and the RAVPower 26800 PD. Big batteries can take forever to recharge—when we test USB battery packs, we regularly have to give the large ones more than 10 hours to completely recharge between tests. As a result, the Anker model’s inclusion of a PD-capable wall charger is what allowed it to clinch our top-pick slot. PD charging is two and a half times faster than that of legacy USB, and twice as fast as standard USB-C charging: You can fully recharge our Anker pick in about four hours from the included charger. Though the RAVPower pack can recharge almost as fast using a proprietary Quick Charge 3.0 charger, that charger isn’t included in the box, and we don’t expect Quick Charge 3.0 to be as universal as USB-C PD.
Any PD-capable pack meant to charge a laptop needs to have a huge capacity, and both the battery packs we tried were equal in that regard: 26,800 mAh, or roughly 100 Wh. That means that a 13-inch laptop such as a MacBook Pro or a Dell XPS 13 should get one and a half to two full charges from either pack. We’ve tested loads of battery packs from both companies over the past few years, and their capacity claims are accurate if you account for some basic inefficiencies present in all battery packs. You can expect to get 90 percent or more of the advertised power from either pack when using it continuously.
Of course, you can use the massive amount of power stored in our pick to charge smartphones and smaller devices, too. If you’re traveling and you forget a wall charger, the Anker PowerCore+ 26800 PD could charge your smartphone every day for most of a week. But the size and weight of the battery make it prohibitive for most people to carry every day.
RAVPower and Anker both make excellent black rectangles, despite there not having been many advances in parallelogram design the past few years. Battery gauges aren’t a big deal when you’re deciding between different packs, but it is nice that the Anker model’s gauge has a 10-segment LED instead of the less-precise four-segment bar on the RAVPower battery. Anker’s aluminum housing makes that model a bit heavier but also a bit more durable. The RAVPower pack’s lighter, plastic body got a few scuffs during the course of our testing.
Anker offers phone support, an option that RAVPower doesn’t provide, but both companies have a reputation for prompt and fair responses to email and online support requests. In addition to the product quality, support responsiveness is a big reason we recommend these two brands again and again. Anker backs all of its battery packs with a simple, 18-month warranty that includes return shipping if the item needs to be replaced. That’s a bit better than the standard RAVPower warranty, which covers shipping for only the first six months and replacements for only 12 months (though the company extends the latter coverage to 24 months if you register your item).
What to look forward to
Right now, you can’t find many USB-C battery packs out there. Mobile battery packs are still predominantly USB-A, so you don’t get much choice in price, size, or capacity among USB-C models. Similarly, only a few laptop-ready USB-C battery packs are available, and those are limited to 30 W output. We’ve reached out to some manufacturers to get details on future models, but we don’t have many specifics to confirm. Anker would confirm only that it had “smaller USB-C batteries planned for the near future” and that it “[did] not have any plans for higher capacity/output batteries.” RAVPower didn’t respond to our inquiry.
The Indiegogo-backed Lifepowr A3 is the only USB-C PD battery pack we know of that promises to exceed the 30 W output of our top pick—the makers of this unreleased model claim that it will support the full 100 W possible under the USB-C PD standard. The new battery pack is expected to ship to backers in November or December 2017, and will sell for $300.
Mophie released a new Apple-exclusive battery for use with USB-C MacBooks. The Powerstation USB-C XXL is rated for a 30 W output, same as our top pick, and Mophie claims that it can extend the life of a laptop by 14 hours. The new battery pack also includes an additional high-output USB-A port, so you can charge a second device simultaneously.
Flying with batteries
Though USB battery packs could be considered personal electronic devices, you should assume that authorities will regard the pack as a spare battery and subject it to more stringent rules. For example, the FAA allows passengers to bring spare batteries in carry-on bags but not in checked luggage. (If you need to gate-check a planned carry-on bag, you are legally required to shift any lithium-ion batteries from that bag to your actual carry-on.) There is no limit to the number of batteries you can carry for personal use, so long as each has a capacity of 100 watt-hours or less. All the batteries we reviewed for this guide have capacities that fall beneath that threshold.
Standard USB-C charging for mobile devices
The Jackery Titan S was one of the first USB-C battery packs available from a trusted manufacturer, and it’s still a great battery with a ton of capacity for the price. But while the Titan S is the size of our PD-capable pick from Anker, it supports only the slower mobile-friendly speeds of our pick from Tronsmart. If you need a lot of USB-C power for tablets and smartphones—say, when you want to share with a team in the field, or when you’re traveling for long periods of time—the Titan S is a fine pack. But it’s not the best choice for most people anymore.
During our research, the Tylt Flipstick was the only truly pocketable USB-C pack we came across. But we didn’t test this tiny power bank because it’s hamstrung by particularly slow output: Despite an integrated USB-C cable, the Flipstick will charge a device at only half the speed of legacy USB chargers, at about 5 W (1 A / 5 V). Given the high price, we don’t think this model is worth it.
The Vinsic 20000mAh Power Bank comes closer in size to our laptop-ready PD pick from Anker but offers only the mobile-device output of our smaller pick from Tronsmart. Even though this Vinsic pack is twice the capacity of our pick, we think the smaller and slightly less expensive Tronsmart Presto 10400mAh is better suited to everyday use for anyone looking to keep a smartphone or tablet charged.
We dismissed the Lovphone PowerCore 10000, the Orico USB-C 10000mAh Portable External Battery, and the JTD Type-C 10000mAh Portable External Battery without testing because of slow, legacy charging speeds from their USB-C ports.
PD-capable charging for laptops
In our tests the RAVPower 26800 PD Portable Charger performed almost identically to our top pick from Anker in terms of ports, outputs, and capacity. Though it’s about $20 cheaper currently, that’s because it doesn’t include a high-speed charger like Anker’s PD wall charger—you must provide your own charger. If you recharge the RAVPower pack from a slower wall charger you already own, it will take two or three times as long as using RAVPower’s optional Quick Charge 3.0 charger, at least eight hours. (Though the RAVPower pack’s USB-C port can recharge it over PD if you buy a compatible wall charger from another company, RAVPower offers only QC 3.0 wall chargers.) This RAVPower battery is the only one that also has a Micro-USB input port. But if you want a USB-C power bank and make the shift to the newer ports and cables, this option is unlikely to be all that convenient, so we didn’t consider it to be a major benefit. Once the wall chargers are as comparable as the battery packs themselves are, we’d likely consider the competition between the RAVPower pack and the Anker pack to be a toss-up, with price being the deciding factor.