Influence of Flow on Sea-Water Battery Fouling

Persistent ocean monitoring is often limited by the availability of long-duration power sources. This is especially true when studying the deep ocean, where batteries must be designed to specifically resist the high pressure, which can reach 1,000 times the pressure at the surface.

Previous work has demonstrated the potential of seawater batteries, which utilize a consumable metallic anode and a chemically inert cathode. Because ambient seawater serves as the electrolyte and the electrodes are made of abundant metals, this concept has promise as a  low-cost, environmentally safe battery. Moreover, by eliminating the need to contain the electrolyte in a housing, the battery can in principle function at arbitrarily high pressures.

However, seawater batteries have been limited in practice by rapid corrosion and fouling, which reduces their power output.

We study the potential utility of ambient flow currents to delay or prevent passivation and fouling on planar seawater battery configurations. Lab experiments and modeling enable characterization of new operational regimes in which seawater batteries can provide long-duration power for ocean monitoring applications.