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Update: May 2017. While the general advice in this article still holds, we’ve updated the specific model recommendations here.
It almost sounds like a bad joke. Smartphones offer their users a chance to do anything from trading stock to sending e-mail to watching cats fall out of boxes. Despite the best efforts of the manufacturers, however, even the most modern phone can’t withstand an all-out assault on its use for more than a few hours.
Some phones compromise by offering batteries you can change out (don’t forget to charge it!), or perhaps an Ultra Power Savings mode (which completely negates the ‘smart’ aspects of a smartphone). It isn’t always feasible to stay within cord’s length of a wall plug, and trading functionality for power savings isn’t why you got a smartphone to begin with.
So What’s a Smartphone Owner to Do?
Allow me to introduce a device that goes by a few different names. I’ve heard it called mobile backup power, a portable charger, an emergency battery pack, an external battery, or simply a portable power pack. I’ll call it what it is for me – a life-saver.
Whatever you call it, it’s essentially a deck-of-cards-sized battery to power almost anything that’s charged by a USB cord. Think of it like a spare gas can that you keep full in your car for emergencies.
You can charge anywhere from 1 to 4 devices at a time from the stored power inside the battery, then recharge the power pack whenever you can plug in. My wife keeps one in her purse, connected to her smartphone and helping me navigate the back roads of Thailand – Google Maps and GPS can be such a power drain.
A Brief Reminder About Power
Electricity rocks – but your device probably doesn’t like just any type of power. In case eighth-grade science feels like a distant memory, let’s quickly refresh what’s important here.
Most powerpacks are measured in milliamp hours (mAh) – how much juice their battery holds. The bigger the number, the more of a charge it can retain and pass on to your devices.
Cheaper power packs offer up between 2,000 and 5,000 milliamps – typically enough to completely charge your smartphone once, or top it off a couple of times. More expensive devices can offer anywhere from 5,000 to 20,000 milliamps – typically enough to charge multiple smartphones completely or (at the higher end) fully recharge an iPad.
Note the batteries with more milliamps can get to be a bit larger than a deck of cards. Voltage and wattage are important as well, but these kinds of devices tend to adjust their output to the device.
For quick reference, your standard iPhone charger puts out 5 volts, 1.0 amps, and 5 watts. Your standard iPad charger puts out 5.1 volts, 2.1 amps, and 12 watts. If your power pack is under-powered, a tablet will charge slower than molasses rolling uphill or simply refuse to charge.
If the power pack has more than one port, it should indicate which one puts out more juice.
These external batteries tend to hold their charge pretty well. I keep mine in my traveling backpack, and top it off once I get back. Some have LED’s to show their current power level; whatever lights they have, charge them until full after they’ve been used.
Some power packs offer many more milliamps – while more is better, you’ll also want to consider how many USB ports are available. More basic models are stuck with one standard-sized USB port and one mini-USB port (typically used to charge the power pack itself).
As the capacity grows, so do the number of USB ports available. You’ll want to check to ensure the power pack can charge all your devices – some will specifically say what devices they can charge, while others will simply say how much power they can output.
Important note: these devices do not plug directly into the wall!
You’ll need to charge these external power packs with a USB wall adapter / charger and a mini-USB to USB cord. Something like this AmazonBasics offering will do the job for a few dollars, or go for one that can charge two USB ports from one wall plug.
Note that some come with a charging cord, but it isn’t always included — so double-check and add another one to your shopping cart if necessary. I personally keep a couple of cords with the battery itself – one to go from the wall charger to the battery, and one that goes from the battery to my device(s).
Finally, note that these devices will not charge your laptop. To do that requires a lot more juice.
Where to Get One
These devices aren’t expensive by any means – Amazon has plenty on sale starting at less than $10, and most major department stores or electronics stores are bound to have at least a few offerings.
I’ve found them across Southeast Asia pretty easily, though obviously selection will vary. All things being equal, try to get one with two USB ports, and spend a little more to avoid a crappy Chinese knockoff.
There’s plenty of power contained within this unit, and 2 USB ports to power a smartphone and tablet. It also has a built-in LED flashlight.
While I’m personally not a huge fan of the lipstick / cylinder type, this offering gives you the adapters to work with virtually every smartphone on the market and has solid 5 star reviews.
At less than $10, this single-port battery claims to hold enough juice to charge your iPhone twice. Small and light (126g / 4.4 oz), you can put this in almost any pocket. The LED torch is a nice bonus, and is a great everyday sort of tool to ensure that your battery lasts until bedtime.
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Charge EVERYTHING! 4 USB ports each put out up to 2.1 Amps, meaning you can have 4 tablets charging at the same time. 12,000 mAh provides plenty of juice, and the device uses a Li-polymer battery, which is more stable and safer than a typical Li-ion battery. The price you pay for these features? It’s a little larger than some of its competitors.
If you’re going off the grid or taking a trip across the ocean, this monster 50,000 mAh offers a huge boost from its six ports (for laptops, cameras, phones, tablets and any other USB devices).
It’s bigger, heavier and more expensive than many other emergency chargers, but that’s the way it goes when you need this much power in reserve. It does includes the connectors you’ll need, at least.
Add a solar charger to take your electronics off the grid for good — although bear in mind that the bigger the battery, the more time you’ll need in the sun to charge it!
Do you have a favorite emergency charger? Let us know about it in the comments!
Main image via Anton S/Flickr, product images via Amazon and the respective manufacturer