We’ll probably be hearing someday soon that LG will announce world’s first commercial “cable battery,” as their subsidiary, LG Chem, has recently announced progress in that direction. This would enable the use of batteries in textiles, headphones and other places where you couldn’t normally fit any battery nowadays.
The cable battery developed by LG Chem is not as efficient as those having a classic form factor. And flexible batteries have been made before, but without notable performance or practicality.
The research team, led by Je Young Kim, used a spiral electrode design that incorporates the inorganic elements used in classic lithium-ion batteries. Thin strands of copper wire coated with nickel and tin (electrode materials) have been woven into a metal yarn. Then, they wrapped the yarn around a circular rod, removed the rod and stretched the coil to create a strong spring a millimeter in diameter that serves as both the anode and the battery’s structural backbone.
The other parts of the cable battery were then wounded around the anode, and had an aluminum wire serve as the basis of the cathode. Then, they drew the battery through a slurry of lithium cobalt oxide (cathode material), and then dried and wrapped it in protective layers. In the end, electrolyte was poured in, and voila! Here you have a cable battery!
They even knotted the new battery and it still worked. A 25-centimeter strip provided 10 hours of power to a 4th gen iPod Shuffle, whose original battery is advertised for up to 15 hours of music playing (ref).
New electrode materials are now being tested to improve the power outputting abilities of the new battery, and testing the safety of these things in the case of an accident.
However, in the future, these batteries could serve as power buffers for the grid and will probably be able to be implemented inside the very cables that carry DC currents. Who knows, maybe power outages will be a thing of the past with these cable batteries…