The Best Power Banks to Fight off That Blinking Red Bar of Death on Your Phone

The Best Power Banks to Fight off That Blinking Red Bar of Death on Your Phone
Image: Anker
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We’re in awe of the fact that our parents and grandparents used to get around without Google Maps. It no doubt took tons of planning ahead and probably resulted in many a wrong turn. These days, most of us can’t go anywhere without our trusty smartphones. While having a phone is great, having a flat battery is not. But that’s exactly where a power bank can come to your rescue.

For those of us born in Generation X, Y or Z, it feels virtually impossible to go anywhere without a phone. The same goes for choosing the best nearby restaurant to eat at, or figuring out which bus to take home. While you could always resign yourself to bringing your wall charger along, or use a public phone charger, you face two negative caveats.

First of all, no one wants to be that person squatting in the corner of the room, trying to juice up your depleted phone battery. And there’s not always a power point available either.

The other issue is juice jacking, which is a serious security risk to your device. Especially when considering how much of your personal info can be stored in your smartphone. Of course, the latter can always be fixed by a data blocker.

So, if you want to ensure your phone’s battery stays in the green, grab yourself a portable power bank. That way you’ll be prepared for anything.

Here’s everything you should consider when buying a portable phone charger, along with a few of our top picks.

How many recharges will you get?

As smartphones have grown more advanced, with increased battery sizes and more energy-demanding tech, so too has the market for portable chargers. It’s not hard to find a portable charger, but it’s important to make sure it can meet all of your needs.

If you’re just looking to recharge your smartphone, there’s an incredibly rough calculation that you could do in order to determine the number of times you might be able to recharge your phone from a fully charged power bank.

Take, for example, the Samsung Galaxy S21 Ultra, a phone with a 5,000mAh internal battery. A 20,000mAh power bank can recharge it four times if it’s fully charged, right?

Not quite, although you should see more than three recharges if the power bank is relatively new and fully charged for sure.

The realities of power transmission are inherently lossy, and the actual transmission rate of the power will also have an effect on how much charge it’s able to put out on a given device. Just like your smartphone, over time a power bank’s internal battery will also lose capacity, so if you’re using an older model, you might not see full capacity when it comes to juicing up your devices.

How many devices do you need to keep juiced up?

power bank
Image: iStock/Anatoliy Sizov

Most high-capacity power banks feature multiple outputs, which is handy if you’re planning on powering up more than just your smartphone, or if you just want to be nice to your friends and family if they’re caught in a power bind.

It’s worth matching up connector types here too. While USB-A is the common standard, because most charging cables end with that rectangular type plug anyway, there are some power banks that offer up either USB-C or Apple’s Lightning connection points, although the latter is fairly rare in an output sense. When charging up the power bank, you should get a compatible cable whether your device uses micro USB, USB-C or Lightning, but usually not an actual plug charger.

What kind of power output do you need?

There’s a certain universality when it comes to charging smartphones from a power bank, because you can pretty much plug any phone into any power bank and get the electrons flowing.

However, that’s not the full story if you want faster charging, and especially if you need a power bank to back up your laptop’s power supply. Some power banks do support standards such as Qualcomm’s Quick Charge if your phone supports that standard, meaning you can juice up your phone much faster, but there are alternative standards such as Oppo’s VOOC, which aren’t usually called out in power bank specifications. If a power bank can deliver higher wattage to your connected device you may find it charges faster, but it’s not guaranteed.

It’s a little more complex if you want a power bank to keep power flowing to a laptop or other high wattage device. What you want to look for there is a power bank that offers Power Delivery, or PD, as a standard.

With the right mix of power bank, cable and device, it is possible to deliver power to laptops, although this can be a little hit and miss, because the device and the power bank have to effectively negotiate the power delivery level that will be safely used. Many laptops may simply opt to use the power bank as an external power source – so they sap the battery but don’t actually “recharge” while in use – which is a safer option than fusing out your laptop, of course.

The best power banks you can buy

ROMOSS 20,000mAh Portable Charger

power bank
Image: Romoss

ROMOSS’ 20,000mAh charger has QuickCharge support, three output sockets and claims compatibility to recharge the Nintendo Switch.

Where to buy

Amazon ($42.99) | eBay ($31.49)

Anker 20,000mAh Power Bank

Anker power bank
Image: Anker

What we love about this power bank is that is caters to the new USB-C and old micro USB outlets as well as two USB 3.0 ports. You’ll be able to charge at least two devices at the same time at fairly quick speeds.

Where to buy

eBay ($52.99)

Charmast 26,800mAh Power Delivery Power Bank

power bank
Image: Charmast

Charmast’s Power Bank has 26,800mAh to share out and plenty of ways to do so, with two standard USB ports, a USB-C port and a Quick Charge compatible port as well. It’s rated for power delivery at up to 18W, and Charmast claims compatibility with the Nintendo Switch and select Apple MacBook models.

Where to buy

Amazon ($69.99) | eBay ($89.87)

Anker 10,000mAh Slim Power Bank

Anker power bank
Image: Anker

While offering a small mAh compared to other power banks on this list, rest assured this portable charger still packs a punch. It’ll perfectly slide into your pants pocket or backpack and you can even activate its trickle-charging mode to enjoy optimised charging for low power devices such as your earphones cases or speakers.

Where to buy

Amazon ($49.99) | eBay ($45.99)

iMuto 20,000mAh Portable Charger

The Best Power Banks to Fight off That Blinking Red Bar of Death on Your Phone

iMuto’s power bank has 20,000mAh on board, two USB-A type outputs and a simple digital display so you can easily see how much power it has left. It also features an in-built flashlight, so even if your phone is lacking in juice, you could still use it by itself to make your way in the dark.

Where to buy

Amazon ($93) | eBay ($69.99)

OISLE 4,225mAh Magnetic Wireless Mini Power Bank

The Best Power Banks to Fight off That Blinking Red Bar of Death on Your Phone
Image: OISLE

OISLE’s magnetic power bank has got to be one of the most aesthetic and compact portable chargers on the market. This cute little fellow comes in five colours and is about half the size of your phone. Unlike other chargers, its biggest draw is the fact that you don’t have to worry about dealing with a dangling cable as you try to get from A to B. In fact, you can tuck it into your back pocket while you wait rather than fish it out of your bag.

Another cool feature is that the logo lights up in three various colours to indicate how much battery juice remains. However, in comparison to the other portable chargers mentioned, it does have a low capacity of just just 4,225mAh. Translation? Slow charging speed, but ideal for sustaining your phone before its battery completely depletes on your way home.

Where to buy

Amazon ($85.99)

Anker PowerCore 20,000mAh Portable Charger

The Best Power Banks to Fight off That Blinking Red Bar of Death on Your Phone
Image: Anker

Anker is one of the best-regarded consumer tech brands around. If you’re after a portable charger with a bit more juice, the Anker PowerCore 20,000mAh portable charger is a solid battery option. This power bank has two USB-A ports for dual-charging, with a 2.4A output for each port.

Where to buy

Amazon ($99.95) | eBay ($103.89)

Zhonghang 26,800mAh Solar Power Bank

The Best Power Banks to Fight off That Blinking Red Bar of Death on Your Phone
Image: Zhonghang

If you’re someone who spends a lot of time in the great outdoors, you know how important it is to have enough battery power. With a battery capacity of 26,800mAh, the Zhonghang power bank can achieve five to six full charges for most iPhone and Samsung models.

You’re even able to recharge this power bank with sunlight, and it even has an in-built LED flashlight. It also happens to be water-proof, dust-proof, and shock-proof, so it’ll withstand whatever is thrown at it.

Where to buy

Amazon ($69.99) | eBay ($93.29)

ZHAM 33,500mAh Solar Power Bank

The Best Power Banks to Fight off That Blinking Red Bar of Death on Your Phone
Image: ZHAM

Awfully similar to the Zhonghang previously mentioned, the ZHAM Solar Power Bank boasts a 33,500mAh which claims it can charge your iPhone 13 up to six times or your Samsung S8 up to seven times.

Dubbed the “outdoorsy man’s favourite battery bank”, it features an LED flashlight. While you may be tempted to argue your phone already has a torch, your phone definitely doesn’t have four strobe light modes which can help you flash an emergency signal if you’re ever in a pickle.

Where to buy

Amazon ($79.99) | eBay ($110.21)

Editor’s note: Descriptions and features are as taken from manufacturer/seller claims and user reviews on Amazon.