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Continued development of the basic power cell led to electrochemical systems 

 which utilize active cathodes. One of these involves the addition of hydrogen 

 peroxide as a reactant to the electrolyte. The peroxide eliminates the evoluation 

 of hydrogen gas and converts it into usable water for dilution purposes. The 

 changes required from the basic lithium water system are the addition of a 

 thin silver or palladium plating to the iron screen cathode and a system for 

 introducing the perioxide solution to the main electrolyte stream as required 

 by power demands on the battery. The addition of hydrogen peroxide essentially 

 doubles the power and energy that a system can deliver for the same weight of 

 lithium consumed. Approximately 1.1kg (2.5 lbs) of hydrogen peroxide are 

 required per pound of lithium consumed; in practical systems where the peroxide 

 utilization is less than 100 percent if 1.4 to l.Skg (3 to 4 lbs) of 80 percent 

 peroxide per pound of lithium is used. 



The marine application of the lithium power cell has been directed into three 

 utilization modes: a deep-ocean power source, a self-contained deep-ocean 

 power source and a small marine power source. 



Deep Ocean Power Source - The deep-ocean power source application uses the 

 lithium-water couple as a 3.75kW submersible power source for use at ocean 

 depths up to 6,096m (20,000 ft). To date, a subscale power module complete 

 with all ancillary pumps, valves, heat exchangers, and pressure compensation 

 components has been tested at 6,096m (20,000 ft) depths. The application 

 of this power source for 15kW submersible power source has been investigated. 

 The design shows the complete system installed in a 56cm (26 in.) diameter pod. 

 As conceptualized, the system uses four modules (installed in a 66cm (26 in.) 

 diameter cylindrical pod) designed to provide a 20 hour operation and has 

 an estimated dry weight (exclusive of the pod) of 408kg (900 lbs) . Much 

 of the system weight is associated with ancillary components which are 

 not altered as operating time is increased. Hence, the system weight 

 does not increase rapidly. 



Self-contained Deep-Ocean Power - The submersible power supply described 

 above uses seawater from the environment and rejects hydrogen. For some 

 applications, it is desirable to provide a self-contained power source 

 which has a minimal interaction with its environment. The lithium-hydrogen 

 peroxide couple can form the basis of such a system. The three-module system 

 was designed to produce 15kW at 105 V and deliver ISOkWhr. Treated 

 seawater and hydrogen peroxide are carried onboard in reservoirs. The 

 reaction products from battery operations are returned to and stored in 

 these same reservoirs, separated from the primary liquids by flexible 

 membranes in each tank. This closed-system type of operation maintains 

 the system at essentially constant buoyancy. The . only minor change in 

 buoyancy results from the venting overboard of small amounts of gases 

 which occur from nonstoichiometric operation. Other configurations are 

 also available. 



Small Marine Power Source - A prototype version of a small marine power 

 source was built and successfully tested. A laboratory brassboard model 

 of a unit has been used to verify performance capability of the design 

 approach. The battery fits within a hull which is suspended below the 

 ocean's surface by a float. Water for dilution and cooling are drawn 



