A power bank used to be something that'd be nice to have, but these days, they're essential. Between YouTube, Candy Crush, Twitter, Tinder, and Thrifter, it's easier than ever to drain your phone's battery before you know it. Factor in additional batteries for your headphones, speakers, and other gadgets, and you'll quickly realize just how much convenience a good power bank can add to your daily routine.

If you're in the market, or perhaps you want to pick up another portable source of power to keep at work or in your car, check out the Anker PowerCore II Slim 10000mAh Power Bank. It's on sale for $29.99 today at Amazon. That's nearly 20% off the normal cost, and it ships for free as well. We don't see it drop in price often, and today's deal comes within a couple bucks of the best deal we've shared for it.

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Power Up

Anker PowerCore II Slim 10000mAh Power Bank

This itty-bitty power bank packs a punch. It's capable of charging modern smartphones up to three times before needing to be recharged, and it charges them quickly too. Your purchase includes an 18-month warranty.

$29.99 $35.99 $6 off

The deal given is no longer valid and we do not have a better one. However, we have found some similar deals

This highly-rated power bank combines a large capacity with a small footprint. It can charge modern smartphones up to three times in as little as an hour and a half. The slim design slips easily into a pocket, palm, or purse, but you could also stash it in the included travel pouch. Anker includes an 18-month warranty with your order as well.

Note that you'll want to provide your own charging cable with your purchase. This 3-in-1 option from Anker can charge via micro-USB, USB-C, and Lightning, eliminating the need for multiple cables taking up space in your bag.

Gearing up to go on a trip? Whether you're flying cross-country or just hitting the road, there are some other things you might want to pack in your bag. Here are the best travel accessories on the market right now.

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