"Intestinal" Nanowire Batteries Could Store Way More Energy

Researchers at the University of Cambridge have invented a lithium-sulphur battery that mimics the human intestine. The battery would replace now-ubiquitous lithium-ion batteries, and could store up to five times the energy in the same sized battery. If the industry adopts this breakthrough, smartphones, solar energy batteries, other electronics, and perhaps even electric cars could last far longer.

“By taking our inspiration from the natural world, we were able to come up with a solution that we hope will accelerate the development of next-generation batteries,” said Teng Zhao, the study’s lead author.

The human intestines are extremely efficient at absorbing nutrients, in large part due to villi — little wiggly protrusions inside the intestinal tract that greatly increase its surface area, making the system far more efficient. Imitating this biological design in a battery therefore makes sense, but it took researchers until now to figure out how to do so. In theory, a lithium-sulphur battery has a far greater energy density, but breaks down too quickly to make its advantage over lithium-ion worthwhile.

By engineering synthetic villi from “tiny, one-dimensional zinc oxide nanowires grown on a scaffold,” the Cambridge researchers figured out a workaround. The synthetic villi prevent important energy-storing elements from drifting away and becoming unusable after each recharge. Instead, the material gets trapped in the nanowires on the electrode, “keeping them electrochemically accessible and allowing the material to be reused,” a press release states.

“This gets us a long way through the bottleneck which is preventing the development of better batteries,” said Dr. Paul Coxon, a co-author. “Ultimately, we’re just trying to make [our] devices work better, hopefully making our lives a little bit nicer.”

“This is the first time a chemically functional layer with a well-organised nano-architecture has been proposed to trap and reuse the dissolved active materials during battery charging and discharging,” Zhao explained. The resultant energy density could be up to five times greater than that of a lithium-ion battery, meaning your devices will last far longer, and therefore need to be charged far less often. And, given that they’ll need less charging, they’ll be more durable: In other words, they won’t start losing their capacity to maintain a charge after a year.

The development is a proof-of-concept, so lithium-sulphur batteries won’t be finding their way into your devices anytime too soon. But it’s hard to imagine that the electronics industry, and the burgeoning electric vehicle industry, will be able to resist such a technology.