Researchers have developed lightweight "supercapacitors" that can be combined with regular batteries to dramatically boost the power of an electric car.
Quite interesting. I have not looked into supercapacitors yet. But I have heard Elon Musk, founder of Tesla and SpaceX mentioning them several times. He believes they have high potential.

At the start of his carreer he was offered a post in a supercapacitor research team but decided to start Paypal instead, becoming a self made Billionaire later.