Roll up nanowire battery from silicon chips

1. Alexandru Vlad^a,^b,¹, 
2. Arava Leela Mohana Reddy^a,¹, 
3. Anakha Ajayan^a,
4. Neelam Singh^a, 
5. Jean-François Gohy^c, 
6. Sorin Melinte^b, and
7. Pulickel M. Ajayan^a,²

1. 1. Published online before print September 4, 2012, doi:10.1073/pnas.1208638109PNAS September 18, 2012vol. 109 no. 38 15168-15173
   

   Here we report an approach to roll out Li-ion battery components from silicon chips by a continuous and repeatable etch-infiltrate-peel cycle. Vertically aligned silicon nanowires etched from recycled silicon wafers are captured in a polymer matrix that operates as Li⁺ gel-electrolyte and electrode separator and peeled off to make multiple battery devices out of a single wafer. Porous, electrically interconnected copper nanoshells are conformally deposited around the silicon nanowires to stabilize the electrodes over extended cycles and provide efficient current collection. Using the above developed process we demonstrate an operational full cell 3.4 V lithium-polymer silicon nanowire (LIPOSIL) battery which is mechanically flexible and scalable to large dimensions