US Patent 7510802 - Bionanobattery

http://www.freepatentsonline.com/7510802.html

Research into microscopic batteries has developed over the past few years to achieve power sources for microrobotic and implantable medical devices. This patent from NASA is based on a spin-coating technique which takes advantage of self-assembly of proteins to achieve a biological nanobattery. Claim 1 reads:

1. A thin-film electrode material for a bio-nanobattery, which is produced by a process comprising:

consecutively depositing arrays of an iron storage protein ferritin on a substrate, employing a spin self-assembly procedure which comprises alternately depositing a plurality of oppositely-charged ferritin layers on the substrate by first forming a first ferritin layer on the substrate, followed by building a second, oppositely-charged ferritin layer on the top of the first ferritin layer to form a bilayer structure, and continuing to deposit oppositely-charged ferritin layers on top of each other until a desired number of bilayer structures is produced, so that an ordered, uniform, stable and robust electrode material of enhanced packing density is presented, which provides optimal charge density for the bio-nanobattery.