Primary lithium cells liquid cathodes

Lithium Primary Cells, Liquid Cathodes, Fig. 1 Lithium/sulfur dioxide cell... 

Lithium Primary Cells, Liquid Cathodes, Fig. 8 Discharge characteristics of spirally wound Li/SOCl2 D-size battery, medium discharge rate at 20 °C [5]... 

Lithium primary batteries with liquid cathodes are a relatively mature technology. Incremental improvements in capacity and performance may occur through design modifications and the use of new materials such as improved carbons in the passive cathode. The U.S. Army is adopting Lithium/Manganese Dioxide replacements for some of the Lithium/Sulfur Dioxide Batteries listed in Table 1 in certain applications. These replacements provide higher capacity and energy at room temperature but not at lower temperature. See the chapter on Lithium Primary Cells Solid Cathodes in this work. 

Solid Electrolytes. A protected Lithium anode is under development for both primary and secondary batteries that promise much larger capacities. This strategy is illustrated by the Li/seawater primary battery in which a Lithium anode is immersed in a nonaqueous electrolyte, the anolyte, that is separated from seawater contacting a cathode current collector by a Li -ion solid-electrolyte separator. The seawater acts as a liquid cathode. Except for contact with a negative post, the Lithium anode and its anolyte are sealed in a compartment containing a Li -ion solid-electrolyte wall that interfaces the seawater. The anolyte is chemically stable to both the Lithium and the solid electrolyte the solid electrolyte must not be reduced on contact with the Li anode. Moreover, eiflier the seal or the compartment must be compliant to allow for the change in volume of the Lithium on discharge. The seawater is not ccmtained in an open cell, it is contained within a battery in a closed cell. The LF ions from the anode react with water at the cathode current collector ... 

Lithium primary cells and batteries with liquid cathode reactants are all very-high-energy devices, contain toxic and flammable... 

This section focuses on four of the most commercially important cells of both classes of Li primaries two of the most common sohd cathode types,lithium manganese dioxide (Li-Mn02) and lithium carbon monoflouride (Li-(CF) ), and two of the most common liquid cathode types, lithium thionyl chloride (Li-SOCh) and lithium sulfur dioxide (Li-S02). 

Electrolytes are generally lithium salts dissolved in aprotic solvents or added to the liquid electroactive molecules as supporting electrolytes to carry the current through the cell. Before describing a number of primary cells of technical and commercial importance, the general properties of the electrolytes, the lithium anode and the more common cathode materials will be discussed. Secondary cells are discussed in Chapter 7. 

When discussing cathodes for primary cells, it is important to make a distinction between solid materials, mentioned above, and those in which the cathode electrochemical component is not in the physical electrode structure, but rather exist in a liquid or gas state. Examples include zinc air cells, lithium thionyl chloride cells, and lithium sulfur dioxide cells. In each case, the physical cathode stmcture serves as a catalytic reaction... 

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