Laser-structured microarray electrodes for durable stretchable lithium-ion battery

Stretchable lithium-ion batteries (SLIBs) hold great potential as a power source for wearable electronics. A major challenge in the development of SLIBs is fabricating stable and reliable stretchable electrodes. Herein, we develop a novel laser-structured microarray electrodes based SLIBs. An active material film adhered to a planar stretchable current collector is ablated by ultrafast laser into an independent microscale square array, enabling electrodes stretchable. A one-dimensional elastic analytical model is developed to evaluate the stretchability of the microarray electrodes under tensile conditions. The microscale square array adheres to the current collector and keeps intact if the shear stress is less than the adhesion force as well as the tensile stress is less than the tensile strength of the active material. The demonstrated electrodes have a mass active material loading of 10 mg cm-2 and maintain robust electrochemical performance when stretched beyond 500 cycles at 100 % strains. The fabricated SLIBs show a stable capacity of 1.2 mAh cm-2, and over 70 % of initial capacity can be maintained at 100 % strain.