A battery of uses

A new breakthrough in bendable battery technology could lead to a future of flexible mobile devices and even smart clothing.

A group of Korean scientists claims to have developed the world's first bendable lithium-ion batteries. According to the Ministry of Education, Science and Technology, a joint research team led by Professor Lee Sang-young of the Ulsan National Institute of Science and Technology and researchers from nine other institutes succeeded in developing a fluid-like polymer electrolyte that can be used instead of liquid-based electrolytes in rechargeable batteries.

Although a liquid is, by definition, inherently more 'flexible' than a solid, it cannot be compressed -- the key to hydraulic action -- and when used in a battery in the form of liquefied positive and negative electrolytes they need to be contained within traditionally rigid cases reducing flexibility.

Earlier work on the subject replaced the rigid cases with a film that separated the positive and negative liquid electrolytes. However, constant flexing generated heat which was sufficient to melt the film, allowing the positive and negative electrolytes to mix. This causes an explosion.

A range of potential uses, from 'paper' tablets to clothes that charge handsets.

With this latest breakthrough, which essentially turns the electrolytes into self-contained flexible cases, the only explosion could be in the market for flexible smartphones and tablets. At this year's CES, Samsung demonstrated its Youm flexible displays that can be rolled into cylinders and even folded in two. Likewise Queen's University in Canada showcased its 'paper' tablet which is as thin and as textured as a sheet of A4 but is actually a touchscreen tablet interface. However, without an equally flexible battery to support them, both technologies remain orphaned demonstrations of what could be possible.

Though the researchers are quick to stress the flexible battery technology is still at an early stage, this significant move forward could well be enough to make flexible mobile devices -- rather than simply flexible screens -- a reality. And, once devices can mirror the movement and flexibility of clothing, the market for truly wearable technology will start to grow. Batteries can be woven into coats or bags to charge handsets or displays can be built directly into garments of clothing.