Flexible Lithium-ion Battery Innovated in Korea


Korean researchers scored a breakthrough in rechargeable battery development leading up to flexible or bendable lithium-ion batteries, which are primary power sources for practically every consumer electronics gadget sold in the market. The innovation could lead up to batteries that gadget designers could simply stuff in, ones which don't conform to any particular shape, and in the future, even complement flexible displays.

No less than Korea's Ministry of Education, Science and Technology announced the breakthrough, crediting a team of researchers led by Professor Lee Sang-Young of the Ulsan National Institute of Science and Technology and from nine other institutes. Together, the team developed imprintable, fluid-like polymer electrolytes that are used for lithium-ion batteries.

Current lithium-ion batteries load liquefied electrolytes into cubical cases (or cells), which don't allow battery flexibility to a large extant. Designers of sleek tablets, for example, worked their way around by using multiple cells wrapped inside a plastic sheath. The new electrolyte is spread on its case (ideally a durable yet flexible plastic membrane), like jam on a slice of bread, ductile electrodes inserted, and exposed to UV rays for 30 seconds, before wrapping up the casing. Manufacturing batteries with the new method is said to be quicker, and thus less expensive.

In addition to flexibility, the team also fundamentally altered the conventional design, making lithium-ion batteries less prone to explosions. "Conventional lithium-ion batteries that use liquefied electrolytes had safety problems as the film that separates the electrolytes may melt under heat, in which case the positive and negative elements may come in contact, causing an explosion," said an official at the ministry. "We hope our paper helps the early commercialization of flexible mobile devices and safer battery use," said Professor Lee.

The flexible battery, along with recent advances in flexible displays, paves the way toward true e-papers. That leaves just one piece out of the puzzle, flexible high-density ICs. Maybe photonics has the answer?