Self-Powered Desalination Battery for Individual Soldiers

Current soldier Individual Water Treatment Devices (IWTD’s) are limited to use with freshwater sources since they lack desalination capabilities.  State of the art desalination technologies such as reverse osmosis are too energy intensive and heavy for individual soldier applications.  Lynntech has developed a desalination battery that removes salts from feed water as it discharges which eliminates the need for an external power source.  The technology has already been demonstrated to achieve >99.6% salt removal from both brackish and seawater sources.  When combined with existing IWTD components, the proposed desalination battery can provide a universal water purification device capable of treating any source water. The overall objective of the Phase I project was to adapt the desalination battery for individual soldier use.  During the Phase I, Lynntech performed lab-scale tests to optimize the desalination battery chemistry, components, and operating conditions.   Based on test cell data, a full-scale desalination rate of 0.5 L/hr and 1 L/hr was demonstrated for simulated seawater and brackish water, respectively.  Lynntech then fabricated and tested an initial desalination battery prototype that was integrated into a 2.5L hydration bladder design.  The prototype weighed 1.3 lbs, possessed a seawater desalination rate of 0.5 L/hr, and had a product water recovery efficiency of 33%.  The results of the Phase I effort demonstrated strong proof-of-concept that Lynntech’s desalination battery can meet the Army’s individual soldier desalination targets.  During Phase II, Lynntech will continue development of the hydration bladder-based desalination battery with a focus on improving overall performance, reducing costs, and simplifying operation.  Custom components will be developed to increase desalination performance and improve manufacturability.  Extensive testing will be performed with alpha prototypes both simulated and natural seawater and brackish water to determine operational lifetime.  Key performance targets to be met include a desalination rate of >1 L/hr with seawater, weight 135 L of potable water from seawater and brackish water.  The Phase II effort will culminate with the fabrication of pre-production prototypes and field testing under a relevant environment to bring the technology to TRL 7.  A cost and manufacturing plan will then be generated for post-Phase II production efforts.