The ExpertPower 20,000mAh portable charger is the best battery you can get under $20 right now because of its large capacity. You get three USB ports to charge from, and the large capacity will mean you can go a few days without needing to charge the battery itself.

Your best choice for a battery

ExpertPower 20,000 mAh Portable Charer

If you're gonna spend any money on a battery pack, you may as well get the biggest capacity you can.

The main job of a portable battery is to charge your gadgets, and the battery can't do that if it's already dead. This battery offers a generous 20,000 mAh cell, so you can easily go a few days without needing to charge the battery itself — even under the worst conditions.

Who should buy this battery

If you can go a few days without being near a power outlet — whether for camping, road trips or just in case of emergencies — this is the battery for you. The large cell will easily last you the course of a trip, even when charging all of your gadgets.

Is it a good time to buy this battery?

Yes. Batteries are batteries — they don't go through a yearly release cycle like smartphones and laptops do. And even if a new battery does come out, that won't change the capacity of this one at all.

Reasons to buy

  • Largest capacity for this price
  • Three USB-A ports to charge your devices from
  • Two of the USB ports offer faster charging

Reasons not to buy

  • No USB-C

Why you should buy this battery

A battery's one job is to safely charge your devices, and this does just that for a low price. The large, 20,000mAh capacity means you'll be able to charge your smartphone, headphones and even tablet several times over, making this perfect for a camping trip or other weekend excursion.

This battery will charge all of your gadgets multiple times over.

Having three USB-A ports means you can charge more than one gadget at a time, and two of the ports output at 2.1 amps. There's no Qualcomm Quick Charge support, but this should still charge your devices at a reasonable speed.

Other batteries to consider

None of these batteries are going to be significantly cheaper, but if you don't need a huge spare battery, a smaller pack will take less space in your bag or back pocket.

A more compact choice

Anker PowerCore 5000

This battery is super compact, meaning it can easily slip into your pocket.

If you just want a battery that's as small as possible, this one from Anker is for you.

This battery from Anker is perfect if you want something as small as possible. It has enough juice to recharge your phone one time, so you'll need to charge the battery itself every night. It comes in right at $20 for the black version, but the blue, red and white versions are slightly more expensive. There's no official Quick Charge support, but the 2 amp output should charge your device relatively quickly.

Better for campers

FLOUREON Solar Charger

If you're heading to the great outdoors, you may as well get a battery that can charge right at your campsite.

This battery can charge via solar power, perfect in the wilderness.

Solar power may not be as fast as charging from a wall, but it's better than a dead battery. This pack from FLOUREON can charge from the sun's rays, so you'll never have an empty cell. You get two USB-A outputs, and the 10,000 mAh battery means you can charge your gadgets a few times before the power pack itself dies.

Bottom line

Capacity comes before other features in a power pack, and the 20,000mAh battery in ExpertPower's pack is the biggest we could find for this price. Being able to charge multiple gadgets at once is a happy addition as well.

Credits — The team that worked on this guide

Tom Westrick is a U.S.-based freelancer. He's been poking and prodding at Android phones since 2011, and covering various topics for Android Central since 2017. He can often be found with multiple laptops in his backpack and a cup of iced tea in his hand. Follow him on Twitter.

Ara Wagoner is overjoyed to have joined the Android Central team full-time after four years of freelance contributions to the site. Yes, her holster is for a phone not a gun. When she's not building new Android themes and poking Google Assistant with a stick, you can find her gutting pumpkins to brine and bake pumpkin seeds. If you see her without headphones, RUN.

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