I tested a portable battery with graphene heat dissipation - and cracked it open for proof

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Close Home Tech Smartphones Mobile Accessories I tested a portable battery with graphene heat dissipation - and cracked it open for proof The Momax Q.Mag X is one of the best magnetic wireless battery packs I've tested. Written by Adrian Kingsley-Hughes, Senior Contributing EditorSenior Contributing Editor May 21, 2026 at 7:00 a.m. PT

Momax Q.Mag X

4 / 5 Very good

pros and cons

Pros

• Exceptionally thin and light
• Can charge two devices simultaneously
• Keeps cool even when being used hard.

Cons

• Aluminum and glass aren't particularly robust.

$29.99 at Amazon

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There are many "MagSafe" magnetic wireless battery packs on the market. Some are great, some are various grades of dismal. And sometimes, devices are head and shoulders above the rest. These packs are well-built, using quality components, and assembled with care.

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The Momax Q.Mag X is one such power bank. It's thin, it's light, it's stylish, and it's cool -- in every sense of the word.

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Momax Q.Mag X

This is one of the best magnetic power banks that I've tested.

details View at Amazon

It's a good-looking power bank

The Q.Mag X is a 5,000 mAh/19.35 Wh power bank that magnetically clamps to your iPhone to charge it up while you're on the move. The capacity is such that it won't draw attention at airports, and the CCC logo means that it will even make it past the stringent security at Chinese airports. 

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The unit has a premium look and feels good in the hand, thanks to its glass and aluminum construction. It's not the most robust power bank on the market -- for that, you need something like the Nitecore NW5000 or the Dark Energy Poseidon Nano -- but if good looks are what you're after, this is the device for you.

But there's more to the Q.Mag X than good looks. And to keep it looking good, the bank even comes with a microfiber polishing cloth.

Thin, light, and cool

First off, it's thin. In fact, it's spookily thin, at only 8.3 mm/0.33 inches. That's the thickness of a pencil, and it's only fractionally thicker than the thinnest point on an iPhone 17, which is 7.95 mm/0.31 inches thick.

The bank is also very lightweight, at only 125 g/4.4 oz, making it only 5 g/0.18 oz heavier than the carbon fiber-clad Nitecore NW5000. 

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On the front is a 15W Qi2-compatible wireless charger that works with iPhones ranging from the 12 to 17 series, AirPods with the wireless charging case, and Android handsets with wireless charging. For everything else, there's a 20W USB-C port on the bottom. And good news for those with more than one device -- the power bank supports simultaneous wireless and wired charging. 

It also supports pass-through charging, so you can charge a wireless device as the power bank charges, which is perfect for overnight charging. The unit supports all popular charging protocols, and it has the usual built-in safety features. 

The Q.Mag X is also cool during use, surprisingly so for a 15W MagSafe power bank, which can sometimes feel like hand warmers. This device only ever got slightly warm at most. The Amazon listing mentioned graphene heat dissipation, which wouldn't surprise me in the least, as there were no hot spots on the unit either while charging or being charged (I'll get back to this area in a bit).

I really like the Q.Mag X. I know it's just a power bank, but it's so well made. The device perfectly combines beauty and functionality. I've enjoyed using it for the past few weeks when out and about.

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Which is why the next bit broke my heart. Yes, I needed to see if the power bank used graphene for cooling, and there was only one way to find out. 

Time to crack it open

It was time to get the spudger out, be destructive, and look inside (I know I shouldn't be using a metal spudger near a live lithium-ion battery, but I've been doing this for years). I regretted having to do this task, but it had to be done. 

I learned a few things.

First, yes, the battery has a graphene coating. Graphene looks like black paint, but it's a form of carbon with excellent thermal conductivity and infrared emissivity, so it's sprayed onto metals, plastics, and electronics to spread and dissipate heat. 

I also found out that the unit is very well built. It took some getting into, and there's ample sealant, adhesive, and thermal silicone keeping it together. 

Also, Momax hasn't skimped on the parts that you can't see. The components used are top-notch, and it's been put together well.  

ZDNET's buying advice

I've tested a lot of wireless power banks, but the Momax Q.Mag X is a standout, both outside and in. And for just under $30 (the price varies depending on the deals available), it's a steal. You should especially consider one if you often find yourself in heated environments that can put batteries in danger.

If you need more power, Momax have a scaled-up 10,000 mAh version. Same quality, more capacity, for less than $10 more.  

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