You can buy an external battery for your smartphone pretty much anywhere, but it’s harder to get one for your laptop — and it’s even more difficult to find one that’s compatible with a MacBook. But that’s about to change thanks to BatteryBox Slim, an external battery that can recharge all MacBook models and offer some exciting additional features as well.
As the name suggests, the battery is very slim. In fact, it’s even thinner than a MacBook Air. The BatterBox Slim can charge any laptop or USB device, including MagSafe 2 MacBooks (Air and Pro) and the 12-inch Retina MacBook that features just a USB-C port.
The company aims to preserve the life of the laptop’s battery by having the battery power the notebook directly, rather than recharging the internal battery. Furthermore, the USB 3.0 ports can charge other USB devices and the battery acts as a dock when charging a USB-C device like the 12-inch MacBook.
The BatteryBox Slim has a massive capacity of 24,000 mAh and needs 10 to 12 hours to recharge using a regular USB-A charger, while USB-C to USB-C charging reduces charging time to between 4 and 6 hours.
Here’s how much extra battery life this external battery should get you, depending on which device you use:
MacBook Air 13” — 1.5x
MacBook Pro Retina 13” — 1.3x
MacBook Pro Retina 15” — 0.8x
Lenovo Thinkpad Carbon — 1.6x
MacBook 12” (USB-C) — 2.8x
Asus Chromebook Flip — 2.5x
iPad Air 2 — 2.9x
Samsung Galaxy S7 — 7x
LG G5 — 7.4x
iPhone 6 — 11.5x
The battery is available for preorder on the company’s website, priced at $99.99 for the first 1,000 buyers and $109.99 after that. The final retail price will be $139.99, and preordered units are supposed to ship by Christmas.
A video further explaining BatteryBox Slim is embedded below.