Hoping for faster and sustainable batteries

Like many mobile phone users, I have only one cellphone, but keep three chargers handy. I put them in my home, my car and my office to ensure that my iPhone 6 Plus doesn't run out of power anytime, anywhere. If I go out for a meeting or an interview, a portable battery charger is a must-take item, more crucial than a notebook, a pen or a recorder.

Consumers, as well as phone and battery makers, electric-car producers, researchers, environmentalists, and policymakers, have been hoping for a faster, safer, cleaner, cheaper and more sustainable way of powering all the electronic equipment in our lives. Now, the advent of electric cars makes the need more urgent.

Any sign of a technology breakthrough in recharging technology or power supplies easily stirs market enthusiasm.