Theoretical study on the efficiency of nanofluidic batteries

A pressure-gradient-driven flow inside nanofluidic channels that have a surface charge can be used to generate streaming current and potential. This process forms the basis for electro-chemo-mechanical energy conversion in nanofluidic batteries. Here, the efficiency of such batteries was calculated using continuum dynamics. Results showed that (a) the bulk ion concentration to yield maximum efficiency depends on the channel height and surface charge density and (b) the efficiency can be expressed by two-dimensionless parameters when the flow is fully developed and the channel is a unipolar solution of counter ions. (c) 2006 Elsevier B.V. All rights reserved.