Our tablets have become such integral parts of our lives that running out of power can be a major disaster. That’s why the security of a robust backup battery is so important.
There are a bunch of options on the market designed for phones, but these generally don’t have enough juice to give a tablet a significant recharge. Instead, tablet users need something like the Justin 10,000 mAh Power Bank from Innovative Technology.
Build & Design
It’s unfortunate there’s no such thing as a small and light 10,000 mAh battery. Still, the one that’s part of the Justin series comes about as close as it can. The power bank is 5.6 x 2.9 x 0.6 inches and 8.7 ounces. That means it’s not really pocketable, but fits easily in a gear bag or purse.
As for the appearance, it’s shiny black plastic with silver trim with rounded edges.
There are two full-size USB ports on the bottom edge. One can provide 2.1 A of power, which makes it best for tablets, while the other provides 1 A and is therefore right for phones. Both can be used for either device, though they aren’t optimized well.
There’s a micro-USB port on the right side, used to recharge the Justin Power Bank itself.
On the front is a set of four blue LEDs that show the level of charge available. Next to this is a On button. There’s no Off button – if nothing is connected to this external battery for a few seconds it turns itself off.
One cannot simply compare the amount of power stored in an external battery to the amount in a tablet’s internal one to find out how many times one can recharge the other, as a considerable amount of power is always lost in the transfer.
In our real-world tests, the Justin 10,000 mAh Power Bank was capable of giving the 8,827 mAh battery in an Apple iPad Air a 70% charge. Our tests also showed that the Amazon Fire HDX 8.9, which has a 4,500 mAh internal battery, can be charged 130% by Innovative Technology’s product.
It should be noted that this isn’t a flaw specific to this device – no external battery is 100% efficient in transferring stored power to a second battery.
Testing an alternate use case, the Justin Power Bank kept an iPad Air fully charged for an entire 8-hour work day, and still had more than a 50% charge at the end.
Recharging this external battery is a lengthy process, taking about 14 hours to go from empty to full when hooked to a 2.1 A USB outlet.
Big storms can lead to lengthy power outages, and with the TV unavailable a tablet can be a great way to keep entertained … but not if its battery runs out. An external battery could also save the day if there’s a project for work or school that must be finished when the Blizzard of 2015 is going on.
The Innovative Technology Justin 10,000 mAh Power Bank (JB-30-10000) can add many hours to a tablet’s life before it needs to be plugged into a wall again, and it can simultaneously recharge a phone or second tablet.
This accessory sells for about $40, and is widely available online.