Stanford researchers invent transparent li ion battery

New battery technology that drops visible materials like copper and aluminum could bring see-through gadgets a step closer, scientists say.

Batteries used in consumer electronics could get a facelift if Stanford researchers get their transparent battery commercialized.Photo by Stanford University

Like the idea of a fully transparent cell phone, e-reader, or other device?

Stanford University graduate student Yuan Yang has come up with a way to make a see-through lithium ion battery, and it could pave the way for completely see-through flexible electronics (some partially transparent gadgets already exist). Developed in conjunction with Yi Cui, a professor of photon science at the SLAC National Accelerator Laboratory, the battery would cost nearly the same as a regular battery if produced on a mass scale, the creators say.

So how does one make a see-through power source? According to Stanford News, "Yang and Cui devised a mesh-like framework for the battery electrodes, with each 'line' in the grid being approximately 35 microns wide. Light passes through the transparent gaps between the gridlines; because the individual lines are so thin, the entire meshwork area appears transparent."

Stanford graduate student Yuan Yang holds a transparent battery.Photo by Stanford/L.A. Cicero

Yang details the research in the July 25 edition of the Proceedings of the National Academy of Sciences. The cost of developing a clear battery apparently isn't very complicated, especially since visible items like copper and aluminum can't be used.

To solve this issue, the researchers evaporated a metal film over micron-size trenches of polydimethylsiloxane (a compound found in silicone that's used in plastic surgery and contact lenses). Several other substances were included in the mix to create the nearly invisible battery, including some really fancy well-positioned electrolytes.

What's truly fascinating about this research is that the materials in the battery are very flexible, meaning that flexible OLED wristwatch or laptop might come sooner than you think.

At least one problem still remains: The battery provides about half the power of a lithium ion equivalent. "The energy density is currently lower than lithium batteries," Yang said. "It is comparable to nickel-cadmium batteries right now."

The duo, joined by Stanford students Sangmoo Jeong, Liangbing Hu, Hui Wu, and Seok Woo Lee, believe they can overcome that challenge in time as materials science advances. The group has big aspirations, with a patent filing already complete, and some even bigger dreams.

"It just looks cool," Cui said. "I want to talk to Steve Jobs about this. I want a transparent iPhone!"