The Korea Advanced Institute of Science and Technology (KAIST) announced on March 17 that the team of professor Choi Jang-wook at its Graduate School of EEWS and Korea Research Institute of Standards and Science (KRISS) professor Song Jae-yong developed a flexible lithium-ion battery that is thinner than a credit card and supports wireless charging.
Existing lithium-ion batteries have their own limits in terms of thickness because their anodes, separation membranes, and cathodes have to be stacked. Besides, the friction between the layers has resulted in the peeling of electrode films, performance deterioration, and inflexibility.
However, the research team arranged the anode and cathode collinearly on the same surface, instead of stacking them, and removed the separation membrane. Then, it placed a partition wall between the two in order to avoid a short circuit. The team conducted bending tests more than 5,000 times to make sure that the novel electrode structure offers a higher level of flexibility while maintaining battery performance.
The new battery is expected to be applied to skin sensors, smart cards, and medical patches. In addition, the research team succeeded in developing wireless charging technology by applying a solar cell and electromagnetic induction to the battery.
At present, the team is working on mass production techniques for a coplanar battery in combination with printing techniques. Its ultimate goal is to produce electronics products such as batteries and semiconductor chips by means of 3D printers. Details of the research are available on the March 6 online edition of Nano Letters.