Stretchable lithium-air batteries for wearable electronics

The development of stretchable energy storage devices with a high energy density is critical while it remains a challenge for the next-generation wearable electronics. Lithium-air batteries could theoretically provide a high energy density, but they are generally bulky and inflexible with poor cycle performance as well as exhibit volatilization and leakage of liquid electrolyte, which has largely limited their applications. Herein, for the first time, a new flexible and stretchable lithium-air battery has been developed by designing a rippled air electrode made of aligned carbon nanotube sheets, a lithium array electrode and a polymer gel electrolyte. It exhibits excellent electrochemical properties including high energy density, and the high electrochemical performances are well maintained under various deformations such as bending, twisting and stretching. This lithium-air battery is demonstrated to be promising in a variety of fields, particularly, wearable electronics.