The 7 Best Portable Power Banks For Travel in 2021
In a previous post we addressed many of the basic questions about power banks, also known as external battery packs or portable USB chargers.
We discussed what they are, a bit about their history, why they’re becoming so essential for travel and the most important factors to consider when buying one for the road.
If you don’t know much about power banks or aren’t well versed in the industry jargon, we recommend you go and read that article first, because otherwise this article may not make complete sense to you.
But if you already know your power bank ABCs and you’re looking for details reviews and comparisons between the best power banks on the market, then you’re in the right place and you should keep reading.
We haven’t personally tested all of the power banks listed below, but for the ones that we haven’t used, we have conducted an awful lot of research and pored over hundreds of user reviews.
With all this information at our disposal we’ve been able to narrow down the hundreds of candidates out there to a shortlist of the top 7 seven power banks for travel.
So without further ado, here are the 7 best power banks for travel in 2020.
1. Anker PowerCore 10000
Dimensions: 2.4 x 3.6 x 0.9 inches (6 x 9.2 x 2.2 cm)
Capacity: 10,000 mAh
Weight:6.4 oz (181.4 g)
Colour: Black, red, white
Battery type: Lithium ion
Input: 2A (max)
Smaller than a deck of cards and as light a baseball, with a charging capacity of 10,000 mAh, the Anker PowerCore 10,000 claims to be 20% lighter than other portable USB chargers with the same capacity.
The product certainly packs a powerful punch for its modest size and weight, making it an ideal companion for the lightweight traveller.
It’s also one of the most popular power banks on the market, with over 20 million happy users and counting. Anker claims to be America’s leading USB charging brand.
The unit stores enough juice to charge an iPhone 8 almost three and a half times or a Samsung Galaxy S8 two and a half times. It’ll charge most tablets once. Premium LG battery cells are used to ensure power, safety and reliability.
The charging technologies used are Anker’s exclusive PowerIQ and VoltageBoost, which combine to ensure fast charging speeds of up to 2.4 amps. Qualcomm Quick Charge is not supported.
If you’re curious about what these two technologies do, basically:
PowerIQ identifies the device that’s connected and uses this information to deliver an optimized, high-speed charge up to 2A.
VoltageBoost compensates when the charger encounters resistance due to long or old cables and ensures a consistent top-speed charging rate.
This power bank will bring most smartphones to a full charge in under 90 minutes, while most users report that it takes 2-3 hours to fully charge the power bank from the mains. That’s fast.
Four blue LED indicator lights are displayed after pressing the power button, which indicate the amount of charge left in the power bank.
The device has a single USB charging port, so you won’t be able to use it to charge multiple devices simultaneously, though that shouldn’t be an issue for most travellers.
The Anker PowerCore 10,000 is not capable of pass-through charging, which is where you can recharge the power bank from the mains while simultaneously charging your device from the power bank (charging and discharging the unit simultaneously).
For peace of mind, the power bank is fitted with a MultiProtect safety system. It has an array of advanced safety features, in addition to basic safety features like surge protection and short circuit protection.
Adventure travellers will also be pleased to know that this power bank excels in terms of its sturdiness and durability.
The product has a rugged double-layer shell, with the inner layer built from fire-resistant polycarbonate and each unit must pass extreme shock, temperature and vibration tests before being shipped out.
The product also backed by a generous 18-month warranty, demonstrating that Anker have great confidence in their product.
Also included with the purchase is a micro USB cable, a travel pouch and a welcome guide. USB-C and lightning cables for iPhone/iPad are sold separately.
Anker’s customer service is reported by many people to be outstanding and most reviewers on Amazon seem to be pretty elated with most of the company’s power bank products.
- MultiProtect safety system
- Compact and lightweight
- Robust, double-layer shell
- Generous 18-month warranty
- Excellent customer service
- No pass-through charging
- Only charges one device at a time
Is it for you?
If you have a device that’s doesn’t support Qualcomm Quick Charge, and you’re looking for a 10,000 mAh portable USB charger, this power bank is a difficult one to beat, although the Mi Power Bank Pro 10000 (reviewed at the end of this article) might take the cake for some people.
If you do have a device that supports Qualcomm Quick Charge, see the Anker PowerCore Speed 10,000 QC below.
2. Anker PowerCore Speed 10000 QC
Dimensions: 2.48 x 3.94 x 0.87 inches
Capacity: 10,000 mAh
Weight: 7.05 oz (200 g)
Colour: Black, white
Battery type: Lithium ion
Input: 5V = 2A
Output: 24 W (max)
The major difference between this power bank and the previous model, is that this can charge your devices even faster if they’re Qualcomm Quick Charge supported. It’s completely backwards compatible with all versions of Quick Charge.
You can check if your device is supported by downloading this PDF list of supported devices. If your device is not on this list, it’s probably not supported, although new devices are being added to the list all the time.
The Anker PowerCore Speed 10,000 QC is only slightly larger than the previous model and about 19 grams heavier, which isn’t an awful lot.
Like the PowerCore 10,000, this portable charger is compatible with Android, Apple and the vast majority of devices that are charged via USB. The company points out that the product will not provide a high-speed charge for the Asus Zenfone 3.
Even though its nominal capacity is the same as the previous power bank, you might be able to squeeze a little bit more juice out of it for certain devices.
The power bank combines three different charging technologies (Qualcomm Quick Charge 3.0, Power IQ & VoltageBoost) to ensure blazing fast charging speeds.
It has a max output of 24 W and claims to be able to charge compatible devices up to 80% in just 30 minutes and four times faster than standard 1A chargers. You can recharge the battery pack in about 6-7 hours if the charging source has a 2A output or higher.
Like the previous model, it won’t support pass through charging. The company has disabled the feature due to the negative effect it has on the lifespan of the battery.
The PowerCore Speed 10000 QC has all the same safety features as the PowerCore 10,000, including temperature control and protection against short-circuiting and power surges.
As with the PowerCore10000, this external battery pack can charge iPhones and iPads but an Apple charging cable is not included.
- Supports Qualcomm Quick Charge
- MultiProtect safety system
- Robust, double-layer shell
- Generous 18-month warranty
- Excellent customer service
- No pass-through charging
- Only charges one device at a time
- Slightly larger and heavier than the Anker Powercore 10000
Is it for you?
The previously mentioned power bank in our list is perfect if you have a device that doesn’t support Qualcomm Quick Charge.
But if your device does support this technology and you're not averse to spending about 10 bucks extra, it makes more sense to buy a power bank that can take advantage, as you'll then be able to enjoy much faster charging.
3. Asus ZenPower 10050 mAh
Dimensions: 0.9 x 2.3 x 3.6 in (2.2 x 5.9 x 9 cm)
Capacity: 10,050 mAh
Weight: 215 g
Battery type: Lithium ion
First off, let us just clarify that we may be bit biased towards this power bank since it’s the one that we are currently travelling with.
The Asus ZenPower is a popular portable USB charger worldwide, but is especially esteemed in the Asian market. The company’s headquarters are based in Taipei, Taiwan.
Weighing in at just 215 g, which is slightly heavier than the Anker PowerCore 10,000 (181 g), this is another great credit-card sized 10,000 mAh power bank.
The product is less than an inch in thickness and only 3.54 inches in length, making it more than an inch shorter than most smartphones and almost identical dimension-wise to the Anker PowerCore 10,000.
It has a stylish, attractive look afforded by its lightweight, anodized aluminium casing. The unit is ergonomically designed to fit in the palm of your hand.
To protect the charger from scratches and impacts, a soft-touch sleeve called the ZenPower Bumper can be bought separately for it in a range of vibrant colours.
The power bank charges my Moto E4 smartphone, which has a 2,800 mAh battery, a little under three times. It charges the iPhone 6 plus over 2 times, the Zenfone 2 over 2 times and the Zenfone Go over 3 times.
With its single 2.4 A USB output port, the Asus ZenPower will charge most smartphones with high-efficiency in about 2 hours, which is relatively quick. Of course, the single output port means it can only charge one device at time.
The battery pack also supports the ever-elusive pass through charging, so you can use it to charge your device while it’s plugged into the mains.
Some users have reported that the charger’s autocut feature doesn’t work in practice, and that the battery pack continues to slowly discharge instead of cutting the current flow to a fully charged phone.
One minor drawback with this power bank, is that it takes quite a long time to charge from the mains via its micro-USB input port - usually somewhere between 6-8 hours.
However, this is the length of time that most people sleep for, so it shouldn’t be an issue if you charge it overnight.
You will have to use your phone’s charging cable to charge the battery pack from the mains, as the provided USB to micro USB cable is very short (about 7 inches long). However, this same cable works fine for charging your device from the power bank.
The Asus ZenPower also comes with inbuilt PowerSafe Technology, which has 11 layers of protection, namely temperature protection, input overvoltage protection, output overvoltage protection, short circuit protection, input reverse direction protection, over charge/over discharge protection, output overcurrent protection, Cell PTC Protection, adapter protection and finally JEITA Protection, which monitors ambient temperatures during charging and adjusts the current accordingly.
With JEITA Protection, the capacity of the battery decreases much more slowly over time, increasing the lifespan of the battery by 1.8 times.
The Asus ZenPower has an impressive 9 international safety certifications,as well as meeting the IEC 60950-1 standard.
In the box also comes a user manual and short (7-8 inch long) USB to micro USB charging cable. You also have a 6-month manufacturer warranty from the date of purchase.
- Fast charging of your devices
- Stylish, ergonomic design
- Comes in five colours
- High emphasis on safety
- Supports pass-through charging
- Autocut feature may not work
- Relatively slow to recharge from the mains
- Only charges one device at a time
Is it for you?
As we mentioned before, this is the power bank we’re currently using, and we are very happy with it.
But admittedly there’s not a whole lot to set it apart from the other 10,000 mAh power banks that we’ve reviewed in this article, and it is about 10 bucks dearer than the Anker PowerCore 10000, which has similar specs.
If you’re looking for a 10,000 mAh power bank, we would say that this product would be a great choice if you prioritize advanced safety features, customization or really need to have pass-through charging.
4. Anker PowerCore 5000
Dimensions: 4.3 x 1.3 x 1.3 inches (10.8 x 3.3 x 3.3 cm)
Capacity: 5,000 mAh
Weight: 4.8 oz (136g)
Battery type: Lithium ion
Output: 5V = 2A
Input: 5V = 2A
The Anker PowerCore 5000 is an ultra-compact, portable and stylish power bank that simultaneously oozes both simplicity and sophistication, with an unusual, yet attractive cylindrical shape chosen to maximize space efficiency.
At just 4.2 inches long, it’s an inch shorter than most smartphones and will fit neatly inside any pocket or backpack compartment.
The unit is powerful enough to charge an iPhone 6s twice, a Samsung S6 1.3 times and an iPad mini 4 0.6 times. Charging it up via the micro-USB 2A input port will usually take about 4-5 hours, which is pretty reasonable.
Understandably for an external battery pack of this size, it has a single output port, so don’t expect to be able to charge more than one device at a time with it.
Like the Anker PowerCore 10000, it combines the company’s exclusive PowerIQ and Voltage Boost charging technologies to optimize charging speed, safety and efficiency.
The power bank comes in the box with a 2 ft USB-A to micro-USB cable, a travel pouch to carry everything in, and a welcome guide.
- Extremely portable (pocket-friendly)
- Uses the same charging technologies as other Anker power banks
- Attractive cylindrical shape
- 5,000 mAh will be insufficient juice for some people
- Has only one output port
Is it for you?
Not every traveller needs a 10,000+ mAh power bank.
If your mobile device already has a long-lasting battery, or if you don’t use your phone much while on the move, you can probably make do with a lower capacity portable charger.
So if you’re in this boat, and you’d also prefer an ultra-light and ultra-portable power bank, the Anker PowerCore 5000 is likely to be right up your alley.
5. RAVPower 22000 mAh Power Bank
Dimensions: 6.5 x 2.8 x 0.9 inches
Capacity: 22,000 mAh
Weight: 14.53 oz (412 g)
Colour: Black, white, red, blue
Battery type: Lithium polymer
Output: 5V = 5.8 A (total for 3 ports)
Input: 5V = 2.4 A
The RAVPower is a slightly larger, significantly heavier and much higher-capacity power bank than the other ones on this list, so it will best suit the type of traveller that’s a device
addict power user.
At 6.5 inches in length, 2.76 in width and 0.9 in thickness, the power bank isn't much larger than the average smartphone, though it's certainly a lot chunkier (not pocket-friendly) and the weight is closer to that of a tablet.
With its colossal 22,000 mAh battery, the RAVPower 22000 will quickly charge an iPhone 7 about 8 times, a Galaxy S7 up to 5 times, and an iPad Mini more than 3 times. Once fully charged, there’s enough juice in this thing to get most travellers through an entire week, assuming moderate use.
In addition to smartphones and tablets, this external battery pack can also charge speakers and cameras.
The inbuilt Panasonic Smart IC frequency technology helps to provide a stable and higher current conversion. Note that it doesn’t support Qualcomm Quick Charge.
The power bank takes about 12-13 hours to recharge (understandable given its capacity) when hooked up to the mains, so it’s best to charge it overnight.
The product also supports pass through charging, so you can charge your device from the power bank while the unit is charging from the mains. However, the manufacturer warns against this practice, as it could reduce the battery lifespan of both the power bank and your device.
The high density Li-Polymer battery that this power bank uses are superior to traditional 18650 cells in terms of efficiency, performance and safety.
The battery supposedly retains 70-80% of its capacity after 500 charge cycles and is good for over 1000 cycles.
One cool thing about the RAVPower 22000 is that it has three iSmart 2.0 USB charging ports at one end, giving it the capability to charge three devices simultaneously.
iSmart 2.0 is a technology that minimizes charging time by adjusting the current and voltage. Each charging port puts out a maximum current of 2.4 A, so the total current output is 5.8 A.
The RAVPower 22000 is a high quality, durable product, with a UL94 V-0 fire-resistant thermoplastic alloy (PC-ABS) shell, which is also used by Mercedes Benz, BMW and other car manufacturers in their luxury cars.
As regards safety features, the battery pack has an MCU (multipoint control unit), which protects it from high-temperatures, over-charging and short-circuiting. It also has an inbuilt surge protection IC (integrated circuit).
Also inside the box is a user manual, two micro-USB charging cables, a carry pouch and a lifetime warranty card.
You get a 12-month warranty with this product, which can be extended for an additional 6 months if you register your product on the RAVPower website at product registration.
- Huge 20,000 mAh capacity
- 3 output ports for charging multiple devices simultaneously
- High quality, sturdy design
- Long-lasting lithium polymer battery
- Pretty heavy
- Not pocket-friendly
Is it for you?
If you need a portable charger that can charge multiple devices simultaneously or that can handle bigger devices like tablets, iPads and cameras, and you can justify the price and weight of this charger, then it might just be what the doctor ordered.
This power bank would also be a practical portable charging solution for a travelling duo or couple who aren't particularly heavy device users, and who would be willing to share a single power bank between them.
6. Dizaul 5000 mAh Solar Power Bank
Dimensions: 2.76 x 5.59 x 0.55 inches (14.3 x 7.5 x 1.5 cm)
Capacity: 5000 mAh
Weight: 4 oz (113 g)
Colour: Black, Blue, Green, Yellow
Battery type: Lithium ion
Output: 5V/2.4A (max)
The Dizaul 500 mAh Portable Solar Power Bank is the perfect companion for the outdoor-loving or offbeat traveller.
It’s made of eco-friendly silicone rubber and PC-ABS (polycarbonate acrylonitrile butadiene styrene), a superior hybrid material which combines the strength and heat-resistant properties of PC with the flexibility of ABS .
At 5.59 inches long, 2.76 inches wide and 0.55 inches thick, it’s about the size of an ordinary smartphone, albeit a bit chunkier so it’ll easily slide into pockets, sleeves and backpacks.
It’s also remarkably light, weighing in at just 113 grams (4 ounces), which is significantly lighter than any of the other power banks reviewed in this article, and is comparable to the weight of an iPhone.
As this power bank is designed for outdoor use, it’s rugged, shock-resistant and water-resistant, so that it can continue to function properly in the rain. It has a football grain design on the back, which has an anti-skidding effect.
As the product name suggests, this external battery pack can be charged up using the energy of the sun. It achieves this via an inbuilt solar panel that almost takes up the entire surface area on the front face of the unit.
If you’re using solar power to charge this power bank, bear in mind that due to the limited surface area of the 5.5V/1.2 W solar panel, it will only recharge the unit at the very modest rate of 120 mAh.
This means that even an entire day spent in direct sunlight will not fully recharge the power bank and it’ll probably need to be kept in the sun for about two days to reach full capacity. The manufacturer does say that the solar charging is only really intended for emergency use.
For ordinary use, there is also the option to charge the power bank in the typical fashion, and recharging the product from a power outlet normally takes about 6-7 hours via the USB to micro USB cable that comes in the box.
The power bank has two USB output ports, enabling two devices to be charged simultaneously. The ports are protected with rubber caps that help to keep water out and ensure safe charging of your devices.
The battery pack can charge a wide range of devices including smartphones, tablets, GoPro cameras, GPS devices and more.
You can clip the included carabiner into the oval-shaped hole at one end of the unit, making it easy to then hook the power bank onto your backpack or hang it from a tent loop.
Other nice features of this portable USB charger are the smart LED indicator lights and the integrated emergency flashlight, which located near the power button in the top right hand corner.
Also included is a flexible LED light that can be plugged into one of the USB ports and is very useful as a reading light for nighttime when you’re camping.
- Great for the outdoors (rugged & water-resistant)
- Built-in solar panel for emergency charging
- Ultra lightweight
- Two USB ports
- Comes in four colours
- Integrated emergency flashlight
- Included LED reading light
- Solar charging is slow
- Slow to charge from the mains with 1A input
- Capacity could be greater
- Performance can vary between individual products
Is it for you?
If you’re going hiking or trekking in remote areas and won’t have access to a power outlet for an extended period of time, an ordinary power bank without solar charging capabilities might not cut it.
Power banks can quickly run out of juice during multi-day trekking scenarios (especially if you’re using your phone for navigation), and if you’ve no way to recharge them, they become a completely useless and redundant weight inside your backpack.
So if you love the backcountry or frequently find yourself off-grid when you travel, the Dizaul 5000 mAH Portable Solar Power Bank is well worth your consideration.
7. Mi Power Bank Pro 10000 mAh
Dimensions: 5.1 x 2.9 x 0.5 inches (12.9 x 7.5 x 1.26 cm)
Capacity: 10,000 mAh
Weight: 8.5 ounces (223 grams)
Battery type: High density Li-Polymer
Input: 5V/2A, 9V/2A, 12V/1.5A
Output: 5V/2A, 9V/2A, 12V/1.5A
The Mi Power Bank Pro is another really solid 10000 mAh power bank made by Chinese manufacturer Xiaomi.
Over 40 million units have been sold globally and the company claims that to be the global industry leader in portable chargers. A Xiaomi power bank is supposedly sold globally every 1.7 seconds.
In terms of size and dimensions, this portable USB charger is remarkably comparable to that of the average smartphone in terms of length and width, and isn’t a whole lot thicker, so it’ll easily slide into a pocket, purse or backpack.
It weighs in at 223 grams, which is marginally heavier than some of its competitors with the same 10000 mAh charging capacity.
At only 0.49” (14.1 mm) thick, the unit has an elegant, ultra-sleek, 180° ergonomic design and its scratch and fingerprint resistant, double-anodized aluminum casing affords it a polished, matte finish that is smooth to the touch and resistant to sweat, corrosion, daily wear, and physical impacts.
The edges of the power bank are CNC (computer numerical control)-finished, a process typically reserved for premium smartphones.
You’ll find the power button, four LED indicator lights, USB-A output port and the USB-C input port all in a row on the front face of the unit.
The Mi Power Bank Pro 10000 is also notable for its wide compatibility and is capable of charging a wide range of devices, including Android smartphones, tablets, iPhones, iPads, Kindle Fire, Fitbit Fitness Trackers, DJI camera drones, Bluetooth earphones and much more.
With its 10,000 mAh (actual capacity is 6,900 mAh) high density Li-Polymer battery, this external battery pack can charge an iPhone 6 4 times, an iPad Mini 1.4 times, a 3000 mAh Android phone 2.5 times and a Mi 5 2.4 times, via its single USB-A output port.
Compared to Lithium ion batteries, Li-Polymer batteries are safer, have better charging conversion rates and maintain a more stable discharge voltage.
This power bank has a conversion rate up to 93%, which is well above average for an external battery pack, and almost as high as conversion rates get.
The Mi Power Bank Pro 10000 fully supports Qualcomm Quick Charge 2.0 and 3.0 can charge QC compatible devices about 25% faster than most standard 5V/2A power banks.
In addition to 5V/2A charging, it also supports 9V/2A and 12V/1.5A charging and it will intelligently adjust power output up to 18 W, depending on the device connected.
The unit has a low-power charging mode as well, which is entered by double-pressing the power button. This is useful for safely charging low power devices like Bluetooth headsets and fitness trackers.
It can be recharged at 18W from a wall charger via the USB-C input port, so it only takes about 3.5 hours to fully recharge the unit, compared to 5-6 hours for most standard 10,000 mAH power banks, yielding time-savings of up to 40%.
The Mi Power Bank Pro 10000 supports pass through charging and some users claim it can do so without negatively affecting the battery life of the power bank.
Note that you can check the battery status by pressing the power button and checking the four white LED light indicators right next to it. Each light represents 25% of the battery’s total capacity.
The product excels in terms of safety, with 9 layers of circuit chip protection.
The USB smart control and charging/discharging chips built by Texas Instruments guard against overheating batteries, short-circuiting, input overvoltage, output overvoltage, output overcurrent, overcharging and over-discharging and incorrect insertion of the charger.
Imported battery cells are equipped with PTC protective circuits to protect against temperature and current excesses. There’s also a manual reset mechanism via the power button if the charging environment is unstable.
In the box also comes a one-foot long, 2-in-1 USB-A to micro-USB cable with a USB Type-C adapter piece tethered to the micro-USB connector for a wider range of charging options. A lightning cable for connecting to iPhones is not included.
- Ultra-sleek, premium design
- Robust housing
- Low-power charge mode for smartwatches & activity trackers
- Lithium polymer battery
- Supports Qualcomm Quick Charge 2.0 & 3.0
- Dual connector cable for more charging options
- Supports pass through charging
- Only one output port
- Slightly heavier than some of its competitors
Is it for you?
The Mi Power Bank Pro 10000 definitely has a more impressive array of features than its rivals and still comes in at a very competitive price. The only way it falls short is in being slightly heavier than the other power banks we’ve reviewed here.
But if minimizing weight isn’t your utmost priority and you’re looking for a really solid, fully-featured 10,000 mAh power bank, we’d say that this is probably your best option.
Why travel with a power bank?
So why should you travel with a power bank anyway? What's the harm if your phone's battery dies and you can't find any way to charge it?
Well, of course, it probably won't be the end of the world if your phone goes kaput during a trip, but a dead device can really slow things down or cause you a great amount of inconvenience if it dies at the wrong time.
For example, if you're trying to request an Uber to take you from the airport to your hotel and your phone dies when you open the app, that would be really frustrating when you're dying to get to your room and recover from your jet lag.
Or what if you were trying to exchange currency at a dubious shop just after crossing overland into a new country. You're not sure if the owner is offering you a fair exchange rate so you open up your favourite currency app on your phone to confirm, but just at that moment the battery dies. Now the power is back in his hands.
And then there are always those "what ifs", like what if the battery dies when you or somebody else is in real trouble and you're trying to make an emergency phone call? This is why we recommend that travellers carry a power bank in our essential travel safety tips guide.
How to choose a power bank for travel (important factors to consider)
Capacity is perhaps the most important factor to consider when buying a power bank.
Power banks have batteries with varying capacities for storing energy. The higher the capacity, the greater the number of times that the power bank can fully recharge a particular device until the battery is depleted.
Having a power bank with ample capacity is important when you’re travelling, as there will likely be occasions when you’ll be unable to access a working power outlet for a considerable period of time (such as during 40 + hour long train journeys in India where the power outlets on the train refuse to work).
In scenarios like these, a portable battery charger with inferior capacity won’t always cut it – it’s better to have the extra capacity and not need it, than need the extra capacity and not have it.
Power bank capacity is normally measured in milliampere hours, denoted as mAh, though this is a unit of measurement that can be quite misleading. (we discuss why below).
If you only intend to use the power bank to charge your smartphone, we generally recommend buying a power bank with a nominal capacity of 10,000 mAh, as this amount of juice will fully charge most smartphones 3 - 4 times (and most tablets 1- 1.5 times).
A good rule of thumb for travel is to buy a power bank with a stated capacity that’s 3-4 times that of your device’s battery. You will therefore need a power bank with a much greater capacity if you plan to use it to charge a tablet or other device with a larger battery.
Okay, so let’s say your smartphone battery is rated at 2,000 mAh and your power bank is rated at 10,000 mAh. In that case, you should expect it to fully charge your phone five times, right?
The reason for this is that there are various conversion losses and you normally need to knock-off around 25-30% of the nominal capacity to get an estimation of the real working capacity of the power bank.
So for a 10,000 mAh power bank, the real working capacity might be closer to 7,500 mAh and thus it will only charge your 2,000 mAh smartphone battery somewhere between three and four times.
Energy is lost inside the PCB (printed circuit board) of the power bank, in the charging cable and also inside the internal charging circuitry of your device.
These losses usually account for about 10% of the total losses, although high-end power banks can have total conversion losses of less than 10%. Xiaomi power banks for example are known to be particularly efficient.
However be careful when a manufacturer states that the conversion rate is X %, as this number often only refers to the efficiency of the PCB and not the overall conversion rate taking into account all energy losses in the system.
But the biggest loss of capacity comes from the voltage conversion process that occurs inside the power bank. To explain this, we have to first understand what mAh actually means.
The mAh value is not actually measuring the energy storage capacity of the power bank.
What it means is that the power bank can supply a current of 10,000 milliamps for a period of one hour at the particular voltage that the power bank battery supplies.
But because power bank batteries supply 3.7 V and USB supplies 5V, a voltage conversion takes place inside the battery pack when you use it to charge your device.
At the new higher voltage (5V) the power bank can no longer supply 10,000 milliamps of current for one hour, so there’s a reduction in the mAh value of the battery pack.
Therefore if we want to determine how many times a power bank will charge our device, we are really only interested in knowing the mAh value of the power bank at 5V, not the nominal mAh value, which is only valid for 3.7V.
The correct and universal way to measure electrical storage capacity is not with mAh but with watt-hours or Wh, a unit which denotes how much electrical power a battery can supply for one hour.
To calculate the true energy storage capacity of a power bank, we must factor in not only the mAh value, but also the voltage that this can be supplied at.
The formula is:
Watt hours = mAh x Voltage/1000
For more info on how to calculate the real capacity of a power bank, see this page.
There are a few additional factors that can affect the capacity of your power bank.
A power bank that charges devices at faster rates can also incur higher conversion losses, although that’s a trade-off you’re probably willing to make for getting your device charged quicker.
Leaving your power bank in extremely cold or hot environments can also cause it to lose stored energy or can even permanently damage the battery.
Stored energy will also be lost over time if you neglect to use your power bank due to a phenomenon known as self-discharge.
So if you haven’t used your power bank for a few weeks or months, you should plug it back into the charger for a while, even if it was fully charged when you stopped using it.
Carry-on travellers in particular have to consider the weight of a power bank, since rather ungenerous weight limits apply to hand luggage that’s to be taken on board many airlines, and many chargers are not pocket-friendly.
A power bank may not weigh all that much on its own but it could still be the final straw that breaks the camel’s back.
A heavy brick in your pocket is also cumbersome; it forces you to tighten your belt or pants drawstrings to prevent your drawers from ending up around your ankles, and it annoyingly bounces around inside your pocket if you try to run.
Portable battery packs tend to get heavier as their capacity increases, with the 20,000 mAh + chargers starting to become, in our opinion, too unwieldy for travel.
We feel that the 10,000 mAh power banks strike the best balance between charging capacity and weight. A reasonable weight for a power bank of this capacity would be anywhere in the region of 150 – 250 grams.
If you’re a device power user or really need a high-capacity power bank for whatever reason, you may be able to justify carrying something heavier.
In general, the lighter the better but beware of power banks that are abnormally light, as this could be a warning that the inner components, such as the battery or safety mechanisms, are severely compromised.
The general rule here is that smaller is better, as long as the capacity is sufficient for your personal needs.
A compact power bank easily slides into trouser pockets, pouches and backpack compartments and leaves more space in these places for other important items.
You usually don't have to worry about size until you start going above 10,000 mAh, at which point power banks can start to become a bit bulky and cumbersome. I consider 10,000 mAh to be the perfect balance of size and capacity for charging small devices on the go.
If you need a high-capacity power bank to charge multiple devices simultaneously or to charge bigger devices like tablets and laptops, be prepared to carry a significantly bigger battery pack.
Design & aesthetics
The power bank design that you decide to go with depends on personal taste to a large extent, but design can also have important practical consequences and can impact the user-friendliness of the product.
Power banks vary in shape, though most are more or less rectangular with varying degrees of thickness. More seldomly, you’ll come across power banks that are cylindrical, oval (in cross-section), cuboidal or even totally whacky shapes. We've even seen a power bank shaped like a red hot chilli pepper.
A relatively sleek design makes it easy to slip a power bank into a tight pocket or backpack sleeve, though we find the somewhat thicker models still fit just fine in our roomy trouser pockets.
Rounded edges not only look elegant but also allow the power bank to be held comfortably in the hand, which is something you might do if you want to use your phone while it's charging.
Consider the location of the charging ports too. If the input and output ports are situated very close together, it could be difficult to plug cables into both of these ports at the same time.
This might make it difficult to avail of pass-through charging (charging your device from the power bank while the unit simultaneously charges from the mains), even if the power bank supports it.
Aesthetics probably matter more to most of us than we care to admit. Choose a colour and an overall look that you find aesthetically pleasing, so that you don’t regret your decision later. Also, examine the product all over; one face may sport a big logo or brand name that’s going to annoy you.
Glossy, polished surfaces are more vulnerable to scratches and showing up fingerprints than matte surfaces. Remember also that a power bank in a darker colour like black will do a better job at masking scratch marks, fingerprints and damage to the shell.
A flimsy or fragile power bank made of cheap plastic or other inferior materials will do you no favours when you’re travelling.
Instead, you’ll want something robust that’s going to be able to withstand the inevitable drops, knocks and other abuses that accompany life on the road.
Superior power bank shells are constructed from materials like anodized aluminium, polycarbonate, silicone rubber and PC-ABS (polycarbonate acrylonitrile butadiene styrene). Some of these materials have heat resistant or fire-resistant properties. Some power banks also have multi-layered shells for extra reinforcement.
The higher quality battery packs also have to pass rigorous vibration, shock and temperature tests before being shipped out.
If you hear mention of such materials and procedures when reading product descriptions and reviews, that’s all good news.
In general the most rugged and durable portable chargers are the ones designed for outdoor use, camping, trekking etc. but these might come with extra features that you don’t need for everyday travel.
The number and type of ports a power bank has is another factor to consider.
Many power banks have a single output port, and with this kind of battery pack you will only be able to charge one device at a time. That’s fine of course if you only plan to use the power bank to charge one device.
Other power banks, especially the high-capacity models, can have dual output ports, three ports, four ports or more. The advantage of having multiple ports is that you can charge two or more devices simultaneously, which is useful if you travel with multiple devices or you’re sharing a power bank between two or more travel buddies.
The majority of power banks we’ve seen use USB-A ports for output and these are compatible with Qualcomm Quick Charge technology in some models. For input, most power banks have a micro-USB port. You’ll also find USB-C type input ports on some power banks.
The power output of a power bank determines the rate at which it can charge your device.
Charging speed is obviously pretty important, as you surely don’t want to have to wait for hours for your device reach a full charge. It’s far more enjoyable to use your phone when there are no charging cables connected to it.
Portable chargers vary in their maximum electric current output, which is usually measured in Amperes (A).
The current industry standard for power banks is 2A, but some models have a max output of 2.4A and can charge your device even faster, as long as your device will accept that current.
If the power bank can supply more current than your device requires, that is not usually a problem, as your device will just draw as much current as it can handle.
On the other hand, if the power bank is unable to supply the current demanded by your device, it may not charge, or may only charge very slowly.
That is why power banks with high current output are always preferable to the ones with low current output. Avoid battery packs that only supply 1A or less, as these will take too long to charge your device.
There are also many power banks that support Qualcomm Quick Charge, a charging technology integrated with some Snapdragon-powered devices that takes charging speeds beyond the typical limits of USB and to new heights.
If both the power bank and your mobile device support QCC, you can enjoy significantly faster charging than is possible with a 2.4 A charger.
Qualcomm Quick Charge now has five standards (they keep releasing a new one every year) – 1.0, 2.0, 3.0, 4 and 4+, with all of these allowing for faster charging than standard USB chargers. You can learn more about these standards and the differences between them in this article.
Power banks with multiple output ports, which usually happen to be the bigger high-capacity models, will usually have a total current output that is less than the sum of the individual port outputs.
For example if a power bank has 3 output ports, each port might supply 2.4 A when used on its own, but when all three ports are used at the same time, the total output is only 5.4 A, meaning that each port is now only putting out 1.8 A.
With that said, you can find power banks that maintain the full output of each port while charging multiple devices but you can expect to pay a premium for those.
Some battery packs with dual ports have a different output for each port, with the lower output port designed for charging smartphones and the higher output port designed for charging larger devices such as tablets.
Power banks obviously need to be charged in advance of when you expect you might need them. Generally you’ll charge them up overnight from a wall outlet to have them ready for the following day.
It always helps if a power bank recharges swiftly once it’s plugged into a power outlet, especially if you’re waking up in just a few hours.
How quickly a power bank can be recharged depends on its capacity and also the maximum current input it can accept.
High-capacity power banks tend to take longer to charge than the low-capacity chargers because of well, their larger capacity, but many will also accept a higher current input, which speeds up the charging process.
The max current input of most portable chargers will generally fall somewhere between 1A and 2.4 A. The higher the max input, the faster the unit can potentially recharge, but your wall charger and charging cable also need to support the max input. Many AC wall adapters only support 1A, so look for one that can support 2A or 2.4A if your power bank will accept a higher input.
Most power banks will charge up fully in just a couple of hours, while others, especially the high-capacity models, can take the entire night.
What’s the difference between lithium ion, lithium ion polymer and lithium polymer batteries? If you don’t know the answer, you’ll probably become confused when you go to buy a power bank.
Basically, lithium ion batteries are one thing, lithium ion polymer batteries are the same battery technology in a more flexible polymer casing (just repackaged), while lithium polymer batteries use a slightly different technology.
It can be confusing because some manufacturers will claim to use lithium polymer batteries when what they are really using is lithium ion polymer batteries. For more on this, see this page.
From what we can decipher though, at least some of the power bank manufacturers that claim to be using lithium polymer batteries are using them in earnest.
The real lithium polymer batteries use a gel or microporous polymer for the electrolyte instead of the liquid electrolyte that lithium ion batteries use.
They can be made thinner than lithium ion batteries and are said to be safer, but are more costly to manufacture, have a shorter lifespan and may have a lower energy density. Lithium polymer batteries are often found in newer laptops and electric cars, and now seem to be making their way into power banks as well.
Lithium-polymer batteries are generally believed to be safer than lithium-ion batteries, in the sense that they’re less likely to explode or cause a fire.
A general indicator of the battery quality is the grade, with grade A denoting high quality.
Higher quality power banks have built-in protective circuitry (PTC) to guard against overheating, short-circuiting, voltage surges, current surges, and overcharging of your device once it’s fully charged. Although these features may bump up the price, it may be worth paying a little more for the peace of mind that they provide.
A good power bank should also have a number of international safety certifications; the most widely recognized of these is the UL certification.
Power banks that are UL (Underwriters Laboratories) certified are more trustworthy, as it means that they have passed the UL 1642 test where the power bank undergoes rigorous electrical, mechanical, environmental and fire exposure testing and auditing.
LED indicator lights
LED indicator lights are useful, if not strictly essential features of a power bank. Most of the latest models have 3 or 4 of them located near the power button and charging ports.
These lights tell you approximately how much juice is left in the power bank, if it’s currently recharging from a power source, if it’s currently charging your device and other things of that nature.
Your power bank may or may not come with a carry case or travel pouch.
We feel that a pouch is important for added protection from knocks, dust, water and scratches. You can also keep a charging cable inside the pouch so that you don’t have to carry it separately.
If your power bank doesn’t come with a case or pouch don’t worry too much, as you’ll probably be able to buy one separately, either an official one made by the same company or a case made by a third-party manufacturer for that specific power bank.
You can even repurpose a small pouch designed to do something else to fit your power bank. For example, we bought a little zippered coin purse at a souvenir shop in Pushkar, India that fits our Asus ZenPower battery pack like a glove.
Power banks usually offer a warranty period ranging from 6 to 18 months. A long warranty period is always a bonus and suggests that the manufacturer has faith in the longevity of their product. Anker is one battery pack manufacturer that’s known for their generous 18-month warranty periods.
Power banks are pretty simple gadgets to operate and you probably won’t need to contact customer service unless the product has a technical fault.
But if a problem does occur with your portable charger, you’ll definitely be glad you chose a manufacturer with great customer service and quick helpful responses that can help you fix the problem or offer you a swift replacement with no questions asked.
The best way to find out about the quality of the customer service of a manufacturer is to read the reviews beneath their products. If most reviewers sing the praises of the customer service then you’re probably choosing a good company. Anker is one power bank manufacturer that is reputed to have excellent customer service.
While you definitely don’t want to pay an arm and a leg for a power bank, you shouldn’t go too cheap either, lest the quality suffers or you end up with a defective unit.
There are a multitude of suspiciously cheap or lightweight power banks on the market that claim to have high capacities, but these are likely to be of poor build quality, or may have a refurbished battery that will lose its capacity very rapidly. By all means look for a great deal, but as we already mentioned, if a deal looks too good to be true, it probably is.
It especially doesn’t make any sense to buy a dirt-cheap power bank of dubious quality if you have an expensive, high-end device. But if you’re buying one for a cheap throwaway phone, you probably don’t need to worry about quality as much.
A middle ground price is usually your best bet when buying a power bank, as you’ll normally get a nice balance between build quality, capacity, features and price. Expect to pay more for power banks with higher capacities, faster charging speeds, more safety features and better build quality.
Whatever your budget, make sure you’re getting good value for your money.
In this guide we’ve provided you with specs, details and comparisons between what we believe to be the 7 best power banks for travel in 2020.
Hopefully we have given you all the information that you need to make an informed decision and you now have a much better idea about which power bank you'd like to purchase.
Obviously the product you choose will depend on many factors such as value for money, as well as your own individual needs and priorities as a traveller.
We can provide you with all the facts and information but ultimately only you can decide what power bank is right for you.
If you liked this article please share it with other travellers. If you have any questions about power banks please leave us a comment below and we’ll reply to you as soon as possible. And if you already travel with a power bank, we’d love you to leave us a comment with your recommendation!
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Our names are Eoghan and Jili and we hail from Ireland and India respectively.
We are two ardent shoestring budget adventure travellers and have been travelling throughout Asia continuously for the past few years.
Having accrued such a wealth of stories and knowledge from our extraordinary and transformative journey, our mission is now to share everything we've experienced and all of the lessons we've learned with our readers.
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