Review of Maxoak K2 50000mAh Power Bank Battery

This is a review of the Maxoak 50,000mAh behemoth battery bank and external power supply. This isn’t a solar generator like the others but is still capable of powering and charging your phones, tablets and laptops with it’s multi connectors.


We’re reviewing this Maxoak 50,000mAh behemoth of a battery which can power pretty much anything you chuck at it because it’s an alternative to the solar generators. You can’t charge this from a solar panel, which is a shame, we thought you might be able to but we haven’t had any luck with our USB Goal Zero Panels and we’ve read online that other USB solar panels dont charge it either. Either way, we didn’t get it for that, we reviewed it for it’s awesome power and huge battery capacity.

Features & Specs

It can charge all phones and tablets off of USB, digital camera batteries or cameras if they charge by USB. It can also charge the most popular branded laptops, I have a Lenovo G5 and an old Dell and my partner has a Lenovo 13″ laptop and an old Samsung and they all have different charging connectors and they all charge from the Maxoak battery. It won’t charge them all at the same time but it is good enough for a couple of charges.

Smartphones: 10-18 charges

Tablets: 5-10 charges

Laptops: 2+ charges

Outputs: 20V/3A for laptops, 12V/2.5A for cameras and two USB 5V/2.1A and two 5V/1A

Recharge Time: 6 hours from UK wall socket

It is good for over 1000+ charge cycles being lithium polymer, so our guess is that this thing is stuffed with 18650 rechargeable battery cells, the same thing you’ll find in laptops, car batteries and other high power draining electrical items.

Whats in the box: 1 x battery power bank(K2),1 x Home charger, 1 x DC cable, 14 x Laptop charge connector, 1 x Multifunction bag, 1 x Manual


maxoak 50000 battery power bank

Laptops That Can Be Charged

There are two things you need to check if you are getting this to charge laptops out in the field or elsewhere.

  1. Check the list of compliant laptop connectors below that yours is one of them, if so, thats a good start.
  2. Check what current your laptop is charged on, anything above 5A will not work, some laptops are 6A or higher.

E:5.5/1.7mm Acer
F:4.8/1.7mm HP
H:5.0/1.0mm Samsung
I:7.4/0.6mm(or 7.4/5.0mm) DELL/HP
Fordell: 7.4/0.6mm(or 7.4/5.0mm) DELL
K:7.9/0.9mm(or 7.9/5.5mm) IBM/LENOVO
L:3.0/1.1mm Samsung
O:4.5/3.0mm only for HP, not fit for Dell Laptop.
Lenovo: fits for LENOVO laptop with square head with a thread in the middle
(not suitable for Lenovo laptop with half solid and half hollow)
FOR DELL: 4.5*3.0mm Dell laptop with 4.0*3.0mm
N:4.0*1.35mm ASUS laptop with 4.0*1.35mm connector
G:4.0*1.7mm Lenovo laptop with 4.0*1.7mm connector

Charging and Running Electrical Devices

You can run a notebook or laptop with this sufficiently without having a battery in your own laptop, that is just amazing and great for older laptops that have dead batteries that you use in the home like a desktop.

You can charge, like the picture suggests above, multiple devices at the exact same time, which is great if you want to charge a laptop and other USB charged devices.


maxoak k2 50000 power bank battery




Pros & Cons

  • Will charge as much as the Goal Zero Yeti 150 with its 10-18 phone charges (depending on phone), multiple tablet and laptop charges
  • Can charge your digital camera via USB or even its batteries using your camera battery charger
  • You can charge and power multiple devices at the same time, 2 phones, camera batteries and a laptop will all get recharged and powered
  • You can charge or run other electrical devices too, some telescopes, smart watches that need charging or USB headtorches, all should be fine, just check their currents.
  • Comes with a lot of laptop connectors so you can charge yours
  • Quite big, easily the biggest battery bank we have ever seen, but at 50,000 that is to be expected, it’s the size of a small brick, a small flat brick actually
  • Takes a while to recharge itself, approximately 6 hours
  • You cant charge this via a 12v car cigarette lighter nor solar panels, only with UK plug socket mains
  • It can’t charge an Apple laptop and a few high current laptops, please check yours first

Conclusion & where to buy

If you need a battery for an extended stay somewhere, in a cafe all day with your laptop or you’re off on an adventure in the woods for a few days and you’re driving there. This will be great to keep in the car or with you so that you can charge the electrical items you are using on your adventure.

Its bulky so this isn’t going to go backpacking with you, but camping, trips in a campervan, days out with electrical devices, this should cover all of them and more. Your friends will be thanking you when you can all charge your phones at the campsite without any hassle!

MAXOAK 50000mAh 6 Port (5V/12V/ 20V) Portable Battery Charger External Battery Power Bank for Laptop & Notebook (not for Apple Laptop)


8.1" x 5.3" x 1.3"

Martin Shaw
Martin Shaw

Martin is an automotive enthusiast with a deep passion for all things cars. He has spent the last decade immersing himself in the industry, reading up on the latest models, attending car shows, and tinkering with his own vehicles. Loves: family, all things cars (apart from selling them), pizza.

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