Hmm, a wooden battery. This may sound like a bad idea at first, but wood is soft, strong and flexible and it can hold liquid electrolytes. And we're talking about nano-batteries here, so it only takes a microscopic wood fiber to make a complete battery — well, a wood fiber coated in a layer of tin.
Engineers at the University of Maryland are currently working on this innovative, low-cost, environmentally friendly idea. The research team used tiny wood fibers from yellow pine trees to make test batteries — and we mean seriously tiny, the tree fibers are a thousand times thinner than a piece of paper. They use sodium rather than lithium, so the team imagines this battery working best in a large-scale environment, like for storing solar energy at a power plant.
Many of the batteries used today can't handle the swelling and shrinking that happens during the charge and discharge process. But this battery can last longer than most nano-batteries available today, averaging more than 400 charging cycles. It's not quite ready to power your cellphone, but we're just looking at the first generation here, and there's a huge amount of potential for the future.