If your smartphone is constantly running out of battery, a portable power bank (also referred to as a "portable charger" or a "portable battery") is pretty much your only solution short of getting a new one. There are a zillion different options out there, but if you want to charge your smartphone we suggest buying one that is small enough to fit in your pocket.
There are few other things to take into consideration before buying a portable power bank — here's what you should know.
Buy one that uses the same charging port as your smartphone (or laptop).
We recommend buying a portable power bank that uses the same method of charging you already use. If you have an Android smartphone (or laptop that uses USB-C), get a portable power bank that charges via USB-C. If you have an iPhone, get one that charges via Lightning. You can buy a portable power bank that can charge wirelessly, too. This will just make your life way easier using the same cables to charge your smartphone and power bank. I promise.
Buy one that can fast charge.
Most of today's portable power banks are integrated with some type of fast charging technology. The two most popular are Power Delivery (PD) and Qualcomm's Quick Charge. The two technologies are a little bit different. Power Delivery only works with a USB-C to USB-C connection and allows the power bank to better control more watts and deliver more power — basically, they’re able to fast charge larger devices (if those devices support it). Qualcomm's Quick Charge allows your smartphone to charge faster than you would with a traditional power bank (it outputs at 5A rather than 3A).
Buy from a reputable brand.
Finally, you should buy a power bank that's made by a brand you trust. If you go on Amazon or another online marketplace, you'll see a lot of cheap options made by companies that you've never heard of. Stay away. Buy one from a notable brand — such as Anker, Mophie, Aukey or RavPower — and it'll last longer and be more reliable.
Have a new iPhone? Get one that works with MagSafe.
The iPhone 12 and iPhone 13 have a special magnet integrated into them, which Apple calls "MagSafe," that allows that work with an ecosystem of accessories but, maybe more importantly, allows them to charge faster when paired with a compatible MagSafe charger; they can at up to 15-watts rather than 7.5 watts. So if you want to charge your iPhone as fast possible and not deal with a charging cable, you definitely want a portable battery that is fully capable with MagSafe. (For more info, read our guide to the best MagSafe battery packs.)
This PowerCore Sim checks most of our boxes. It's super thin and can easily fit in your pocket. Two, it has a fast and powerful 20W USB-C port that's capable of charging your iPhone 12/13 to about 50-percent in 30 minutes. And it's 10,000mAh capacity is enough to charge whichever smartphone you have several times over (and it's actually more than many other super slim portable batteries on this list). This is a great universal portable battery, however, if you have an iPhone you might want to look at something with an integrated Lightning cable like Mophie's powerstation plus mini (below).
The best thing about the powerstation plus mini is its integrated charging cable with Lightning and micro-USB connections. It means that you don't have to remember to bring a charging cable, which is the biggest hassle and the thing that's most likely to get lost or broken. Throw in the fact that for some reason Amazon is selling it for under $10, and it's a no brainer buy. The only downside is that its 4,000mAh is barely enough to get any smartphone back to 100 percent.
Mophie makes a wide variety of portable power banks and this powerstation with PD is one of its best all-around options. Its 10,000mAh capacity is enough to completely charge your smartphone twice over and it charges via USB-C, which is the same connection as most new-age laptops and Android smartphones. It also has a 18W USB-C output port with Power Deliver (PD) so it's able to fast charge your smartphone.
It's on the expensive side compared to other MagSafe-compatible portable batteries, but Apple's MagSafe Battery Pack comes with some key advantages for the iPhone 12/13. It charges via Lightning and can fast charge (up to 15-watts) when plugged into power. And its battery life can be seen from your iPhone 12 or iPhone 13's Lock Screen and from the Batteries widget.
The powerstation plus is a larger version of the powerstation plus mini, which is our "best budget" pick. It's a 6,040mAh portable battery (compared to the mini's 4,000mAh) and holds enough to charge your iPhone a little more than once over. It also has two color features that are specific to iPhone users. One, it has an integrated Lightning cable that hides nicely into its side. And two, it charges via Lightning, too, which is convenient. Normally $80, you can get this for significantly less right now.
The PowerCore Slim is a 10,000mAh portable battery that's capable of charging most of the latest smartphones tw0-and-a-half times over. It has two input charging ports, micro-USB and USB-C, so it's versatile in the way you can recharge it. Its only output port is a USB-A 2.0. The catch is that it only comes with a micro-USB charging cable — no USB-C cable or wall adapter — which is why it's so affordable.
RavPower is another one of our favorite makers of portable chargers. This pocket-sized option is nice because it supports Power Delivery (PD) and can charge most smartphones faster than other power banks. It also has 20-watt USB-C input that supports PD, so you can recharge it really fast, too. It comes with a USB-C to USB-C cable, but no wall adapter.
Belkin's 10,000mAh portable charger has a built-in stand that's perfect for people who like to watch videos on their smartphone while it charges. And since the stand is retractable, it doesn't make the charge any bulkier. There are two out ports, one USB-C and USB-A, so it's capable of charging two devices at the same time.
There are a number of different MagSafe-compatible portable batteries out there, all of which magnetically attach to your iPhone 12 or iPhone 13 so that you can wirelessly charge it on the go — no need to bring a cable.