Sometimes you need a large capacity powerbank that is compact, charges two phones at once, and will last you (at least) a whole day of charging (for those out of town trips where you need your phone always charged). That’s where the Promate Quantum-20 Ultra-Compact Powerbank comes in. With 20,000mAh capacity, about twice the “standard” 10,000mAh-ish powerbank, but in a “small” body, it’s easy to forget you have it in your bag. At P2,495, it’s a deliberate purchase for those who need a reliable powerbank. Here’s our full review. (We have a video review below if you’re in a hurry.)

Promate Quantum-20 Ultra-Compact 20,000mAh Powerbank Review
Promate Quantum-20 Ultra-Compact 20,000mAh Powerbank Review
Promate Quantum-20 Ultra-Compact 20,000mAh Powerbank Review
Promate Quantum-20 Ultra-Compact 20,000mAh Powerbank Review

Quick overview: the Promate Quantum-20 has a 20,000mAh Lithium-Ion battery with a 5V, 2A input, a 5V, 2.4A (maximum) output, and a 12-hour charging time from zero to full.

Key Features:

  • High-capacity AND compact. While some powerbanks can be thin and light, they won’t last a full day of non-stop charging use like the Quantum-20. Meanwhile, some high capacity ones are just huge and hefty and cumbersome. The Quantum-20 is easy to grab, grip, carry around, and stow away. It also won’t bulk up when inserted into pockets.
  • Charge level indicator at a touch of a button. This is so intuitive. Some powerbanks have a small physical awkwardly-placed button for indicating charge level. Others need to be plugged in for you to see the charge level. The button on the Quantum-20 is huge, up front, and obvious. Press and see the four LED lights. Each ligh indicated about 25% of charge. Simple.

Promate Quantum-20 Ultra-Compact 20,000mAh Powerbank Review

  • Dual USB charging at full capacity. Some powerbanks with dual USB ports won’t charge at max capacity. The Quantum-20 will.
  • Overcharge protection. Your devices will get the right level of charging needed – no undercharging or overcharging.
  • Won’t get uncomfortably warm when in use. The built-it overheating protection means this high capacity powerbank won’t burn a hole in your bag or your bed, a danger parents have the right to worry about.
  • Compatible with a lot of devices – from smartphones and tablets, to game controllers and music players.
  • Promate offers 18-months warranty. Not a lot of powerbank brands offer that. So keep it in mind.
Promate Quantum-20 Ultra-Compact 20,000mAh Powerbank Review
Single device charging. That budget phone is the Kata V6.
Promate Quantum-20 Ultra-Compact 20,000mAh Powerbank Review
Simultaneous charging of two devices. Kata V6 on the left, and LG G5 on the right. Type C cable used on the G5 not included.

Here’s our quick video review:

The few downsides we can think of:

  • No free adaptor tip cable. For that price (P2,495), we wish it came with a charging cable with multiple adaptor tips, like this one. (See image below.) Such a feature would make connecting anything to the Quantum-20 more convenient, so you can also charge an iPhone and a Type C smartphone.

  • Long charging time. The 12-hour charging time, from zero to full capacity, may raise eyebrows (it takes “too long”) but remember that you don’t need it at full capacity everyday, and you can always plug it in before you sleep and unplug it after breakfast. The same “discipline” that applies to charging powerbanks and phones prior to a long trip, applies here.
  • No LED light. There’s no LED lamp to take advantage of that long battery stamina. Like this desklamp-powerbank. (See image below).

  • No Quick Charge 3.0 feature. If your phone and powerbank both had Quick Charge 3.0, then charging is faster. Simply as that. Some powerbanks do offer such a feature. Just not this one.


Where to Buy This High Capacity Powerbank

The Promate Quantum-20 20,000 mAh powerbank sells for P2,495 at Lazada and at Shopee. If you’re a first time Shopee buyer, use the code below to get P80 off on your first purchase.

SwirlingOverCoffee Shopee Unique Code

The Quantum-20 is also available at Abacus, Electroworld, Abenson, Allhome, National Book Store, Workstation, PCiNet Computer, Digital Interface, Allworld, Perfect Shot, TCA DIGITAL SQUARE, The Loop by PMC, Denver’s Computer Shoppe, Concept Computer, Vivocom Technologies, JARGONS COMPUTER, WILCON DEPOT, Globe, and CUBED TECHNOLOGIES.

Promate Quantum-20 Ultra-Compact 20,000mAh Powerbank Review
Contents unboxed

Should you buy it? 

While the price is about three to four times the “standard” 10,000-ish mAh powerbank sold online, remember that few cheap powerbanks offer protection from overheating (heat-resistant design) and overcharging your devices (automatic voltage regulation). And not many 20,000 mAh powerbanks are this compact and easy to hold, neither do most of them offer 18-months warranty. So, if you don’t need the Quick Charge feature, you’ll be happy with the Promate Quantum-20 powerbank.

About Promate

Promate is a digital lifestyle electronic accessory brand focused on delivering the most specialized and original electronic peripheral solutions for Smartphones, Tablets & laptops. Incorporated in the year 2008 and headquartered in Dubai, Promate Technologies has grown to become one of the largest & most awarded provider of accessories for portable devices and digital media. Globally, Promate has a huge market presence in Europe (United Kingdom, Russia, Romania, Germany, Turkey), Middle East (United Arab Emirates, Kuwait, Saudi Arabia, Qatar), South America (Mexico, Brazil, Argentina, Chile, Peru), Asia (India, Vietnam, Philippines), Australia & South Africa just to name a few.

Visit their website (, follow them on Instagram (@promatephil), like their Facebook page (@promatephil), subscribe to their channel on YouTube (, and check out their Lazada store (

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