We recently tested out our top-recommended USB-C battery, the Anker PowerCore+ 20,100 with the Samsung Chromebook Plus. Reports had been great on its use with a variety of USB-C phones, laptops, and tablets, but we wanted to see how well it would work with the latest Chromebook from Samsung.

Anker PowerCore+ 20,100 USB-C External Battery

If you're working on a laptop for an extended period, you'll do well with the Anker PowerCore+ USB-C in your bag as a backup. It doesn't charge as fast as a wall charger, but so far there aren't any reliable, affordable, reasonably sized external batteries that can do this. What it does do is charge a laptop like the Samsung Chromebook Plus slowly while you continue to use it. It's 2.3 inches wide, and can also fast-charge three mobile devices such as phones at once. It comes with an 18-month warranty.

Our assumption is that a laptop user who carries an external battery would like to use that battery to keep working/playing once the laptop's own battery gives out.

We thus ran the battery on a Samsung Chromebook Plus down to zero, until the unit turned off. We then attached the fully charged Anker Powercore+ via a USB-C to USB-C cable. (It's important to push the button on the Anker before doing this, as this tells the battery to charge the connected device, rather than attempt to draw power from it.)

Once connected, the Chromebook Plus could be powered on. The battery indicator on the Chromebook showed (see photo at right) that it was connected to a "low-power charger" and indeed the recharging was slower than if the Chromebook had been connected to a wall outlet.

The Chromebook Plus would obviously charge faster if it were powered off, but we were more interested in seeing how it would do if we were using it (if stuck on a long flight, a marathon work session in a coffee shop, etc.). We thus continued to use the laptop for low intensity tasks (writing for this website, listening to music) while it charged.

After 4 hours and 22 minutes the Anker battery was completely depleted and the Chromebook Plus had reached 84% of its capacity. We would thus expect that if you set out to work somewhere far from a power source, you could get two full working days out of your Chromebook Plus and Anker PowerCore+ if you started with both fully charged.After 4 hours and 22 minutes the Anker battery was completely depleted and the Chromebook Plus had reached 84% of its capacity. We would thus expect that if you set out to work somewhere far from a power source, you could get two full working days out of your Chromebook Plus and Anker PowerCore+ if you started with both fully charged. It would be a bit less if you also used the Anker battery to charge a mobile phone or other device, of course.

The one drawback to the Anker PowerCore+ that we discovered in this test was that the battery automatically started drawing power back away from the Chromebook at the end of the process. This is obviously not ideal — one needs to be vigilant about disconnecting the battery once it is depleted.

Still, as we reported in our main review, the Anker PowerCore+ remains the best USB-C external battery option for now, and gives quite a bit of backup power and autonomy for most normal USB-C laptop, tablet, and phone use.