High-performance, stable, stretchable lithium metal anode for flexible lithium ion batteries

Engineers in Prof. Yi Cui's laboratory have developed a stretchable, stable, high energy density anode to be used in lithium ion batteries that power stretchable electronic devices (e.g., wearable electronics, bendable phones or flexible displays). Until now, the energy density of stretchable lithium ion batteries has been extremely low due to materials with low lithium (Li) storage capabilities, while high performance Li metal has been too brittle for elastic deformation. To enable use of Li metal in stretchable batteries, this technology integrates Li into a hierarchical copper (Cu) spiral which is covered with rubber for flexibility. This simple design makes the whole electrode highly stretchable with stable electrochemical performances during mechanical stretching/releasing cycles. The anode could enable Li ion batteries that can adapt to the dynamic motions of electronic devices while maintaining good electrochemical performance.

Stage of Research
The inventors have demonstrated this anode with a working coin and pouch cell and tested it in over 100 cells. They are continuing their work with plans to create a similar stretchable cathode.