The ZMI PowerPack 20000 is the most useful backup battery you can buy. It packs a huge, 20,000mAh battery that can power a MacBook and two other devices at the same time. Plus, you can quick charge it via USB. And it can even work as a USB data hub.
This 14.29-ounce (405 gram) brick might be overkill for daily juicing of your iPhone, but for everything else it’s amazing.
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ZMI PowerPack 20000 review: One big battery
The ZMI PowerPack 20000 is essentially a huge battery wrapped in a blue-black aluminum skin, with three ports and a button. You use its single USB-C port to charge the unit, and to charge your MacBook or iPad Pro (via USB-C cable). Two USB-A ports can charge any other USB device.
The maximum output tops out at 45 watts. That’s powerful enough for a MacBook, and more than enough to charge the iPad Pro while in use. Because you charge the battery itself via USB-C, charging is fast. You can go from full to empty in a little under four hours.
USB data hub
So far, it’s not really any different from any other USB-C battery pack. But the ZMI PowerPack 20000, which retails for about $70, also works as a USB data hub. Plug your Mac (or iPad) into the USB-C port, then plug a mouse, a USB drive, an SD card reader, a MIDI music peripheral or anything else, into the other two ports, and they will be connected to your computer. To activate the data feature, just double-tap the button on the side of the device.
This is pretty amazing. It means you can use any peripherals while also charging your computer, anywhere you like. On a recent super-long train journey, I used the ZMI to connect the Teenage Engineering OP-Z synth to my iPad. It worked perfectly as both a MIDI connection, and as a USB audio connection. And when iOS 13 arrives and adds USB storage capabilities to the iPad Pro, you’ll be able to hook up storage, too.
One other neat feature: USB battery power is clean. If your audio gear buzzes when you connect it together and power it from a regular USB charger, try using this battery pack instead. I find it eliminates buzz, while still keeping everything charged.
The ZMI comes with a little microfiber pouch, and a couple of USB-C cables (one doubles as a micro USB cable). Put this and a USB-C power brick in your luggage, and you’ll be covered for everything.
Buy from: Amazon