The Mipow Power Cube XS combines a wireless iPhone charger with a portable battery. Put another way, it’s a wireless charger that works wherever you take it, with no power sockets or cables needed.
Be sure to check out our reviews of this innovative but affordable accessory, which launches this week.
Mipow Power Cube XS review
There are two parts to the Power Cube XS, a dock and a detachable wireless power bank and charger.
The dock lives permanently on your desk. It’s an oval that’s 7.2 inches long, 3.8 in. wide and 0.9 inches tall with the bank held in its central cradle. It’s mostly there to send power the portable unit.
The mobile combination power bank and charger is also an oval. This one is 5.7 inches by 2.8 inches. It’s curious that Mipow called this the Power Cube XS when it’s all ovals.
The bottom of the power bank is curved so it slides easily into the dock. A notch in the dock makes it easy to pick up the bank again. There’s a connector on the dock that has to meet one on the portable unit to transfer power, so the power bank only fits in one way.
A leatherette case that fits tightly around the mobile charger comes with this accessory. This helps keep it from getting scratched.
Mipow offers the Power Cube XS in black or white. Our review unit is white, and it matches Apple’s chargers and other accessories very well.
This accessory uses the Qi wireless charging standard, so all that’s necessary to send power to a 2018 or 2017 iPhone model is put it on the power bank.
The top isn’t completely flat, but that doesn’t affect charging in any way. There’s a couple of optional rubberized plastic ovals that can be used to make the iPhone sit a bit more firmly on the power bank, and to make the power bank itself a bit more stable — remember, the bottom is slightly curved — but we found these superfluous.
The Power Cube XS has a touch-sensitive “on” button. A slide of the finger on one side of the power bank activates it. This also lights up a glowing + sign, showing that the accessory is ready to use and also giving a handy indication of exactly where to aim the center of the iPhone for.
There’s no power off button. This device will turn itself off after it’s not sending power to a phone for 60 seconds.
Four illuminated rectangles indicate how much power is left in the battery.
On one end of the dock is a USB-C input port to receive power. Next to this is a USB-A output port, so a second device can be attached here. Perhaps one that can’t wirelessly charge, like an iPad.
Similarly, the portable battery unit has a USB-C input port on one end, and a USB-A output port on the other. This means you can charge the battery pack without the dock, or recharge a non-wireless device with the Power Cube XS wherever you are.
You may have noticed that the dock is really bulky and not actually required to charge the battery pack. Anyone not planning on taking the portable charger with them every day might consider sticking the dock in a drawer and just plugging in the battery. This misses out on the ease of just dropping the battery pack in the dock to recharge it, though.
Mipow Power Cube XS performance
The battery in Mipow’s accessory holds 5000 mAh (18.5 Wh). How much of a charge that will give a phone varies between models, as their battery sizes also vary. We tested the Power Cube XS with an iPhone XS Max, and found it was capable of giving the handset a 68 percent charge.
As Apple’s device has a 3174 mAh (12.08 Wh) battery, this wireless charger is very inefficient… but don’t blame Mipow. Wireless charging wastes a lot of power. It’s convenient, but wasteful.
We tested this external battery’s ability to recharge a handset via its built-in USB-A port. When sending power over a cable, Mipow’s accessory gave the XS Max battery a 104% charge. That took multiple sessions, of course.
Our tests showed that wireless charging increased the battery level in the iPhone XS Max about 15 percent every half an hour. This didn’t change if the accessory is running off battery power or a wall charger. Tests with other wireless chargers have found that this is a typical wireless charging speed. Changing via a cable is actually slower.
Our XS Max will receive wireless power from Mipow’s accessory even when its in a Mujjo Full Leather Wallet. Wireless charging works through this leather case and the leatherette one Mipow supplies with its external battery.
It takes about 2.5 hours too fully recharge the Power Cube XS when it’s placed on its dock.
Mipow Power Cube XS final thoughts
Accessories that can do two jobs are always welcome, and the Power Cube XS is both a wireless charger for your desk and a portable battery. Even better, it can wirelessly power up your iPhone even when in a meeting, in class, etc. And no cables are required to use it.
The design of this sleek accessory matches Apple’s iPhone chargers, and it’s very pocketable.
Just be aware that wireless charging isn’t very efficient. Connecting an iPhone via a cable to the built-in USB-A port will result in more battery power.
We couldn’t find any wireless chargers/batteries to compare this to, but consider the Mophie Charge Stream Travel Kit. This is $40.46 on Amazon, and is just a portable wireless charger without a built-in battery. Or there’s the Mophie Powerstation XXL. This offers a lot more power, but no wireless charging, it’s bulkier, and it’s $59.98 on Amazon.