Session 17: Power Technology
Flexible and Stretchable Power Sources for Wearable Applications
Wednesday, June 21, 2017
4:40 PM - 5:00 PM
Flexible and stretchable power sources are key components of wearable electronic devices that are designed as compliant systems. Developing flexible and stretchable batteries that are safe and exhibit mechanical endurance that is on par with commercial standards remains a challenge. We present a unique approach to construct intrinsically safe silver-zinc batteries with mechanically robust geometries. It relies on utilization of current collectors with enhanced mechanical design such as helical springs and serpentines as a structural support and backbone for the battery components. The batteries based on helical band springs comprised the wire-shaped batteries that are resilient to fatigue and retain specific capacity of 1.2 mAh cm-1 at 0.5C discharge over 17,000 flexure cycles at a 0.5 cm bending radius. Serpentine shaped batteries maintained their specific capacity while being stretched to varying degree and directionality. The batteries were integrated with organic photovoltaic module into wearable bracelet that could harvest and store energy ranging from microwatts to milliwatts depending on illumination. 
1. A. M. Zamarayeva, A. E. Ostfeld, M. Wang, J.K Duey, B. Lechene, I. L. Deckman, G, Davies , D. A. Steingart, A. C. Arias, In Review 2017
Alla Zamarayeva is a graduate researcher in the printed electronics group of Prof. Ana Arias at UC Berkeley. Her research focuses on utilizing printing techniques to construct energy storage devices for powering wearable electronics as well as on printed electrochemical sensors for continuous health monitoring.
University of California Berkeley