While many of us are totally addicted to our smartphones, often the one piece of hardware that we make sure never to leave the house without is our power bank. After all, what good is the handset in your pocket if the battery is dead; you might as well carry around a brick. The power bank evolved from those battery cases developed by companies like Mophie. Remember those early Juice Packs? The first one was made in 2007 for the original Apple iPhone, taking advantage of Apple’s decision (unusual at the time) to seal in the battery that powered the device.
The power bank industry has grown …