Carbon discharge reaction

Figure 18. Discharge mechanism of a Li—SOCij ceii. The cell can operate until the surface of the carbon cathode is fully covered by electronically insulating LiCI and S discharge products. The Li—SO2 cell is also a soluble cathode system with a cell construction similar to that of the Li—SOCI2 cell. It follows a similar discharge reaction where the reaction product is L1S204.

In some cases, the kinetics of the redox charge— discharge reactions can proceed almost as quickly and reversibly as EDL charging. Thin film redox electrodes, based on the lithium intercalation/inser-tion principle such as Li4Ti50i2, exhibit high reversibility and fast kinetics. The Ru02 materials deposited on carbon show pseudo-capacitive charge—... 

If the reactor walls are involved in the discharge reaction, an increase or decrease in carbon monoxide conversion should be observed. The experiments performed with the packed annulus reactor are compared with those of the open annulus reactor in Figure 6 and the experimental data are given in Table II. Within experimental error, no effect of increased reactor surface can be detected. Thus, it appears that the water-gas shift reaction in an ozonizer discharge proceeds via a purely gas phase mechanism. It appears to be a homogeneous reaction. 

The first commercialized Li ion cells used LiCo02 as the positive electrode material. It consists of Li inserted between the cobalt and oxygen layers. The charge and discharge reactions are similar to carbon in that Li is removed and inserted leaving the basic LiCo02 unchanged ... 

This lowers the rate-limiting concentration of OH ions and can affect the anode reaction to produce a heavier and more voluminous metal bicarbonate or carbonate instead of the oxide. The presence of HCOs ions can also result in the formation of anode surface carbonate films that passivate or inhibit the anode discharge reaction, severely limiting the anode discharge reaction s rate-carrying ability. 

The Li-SOCh battery consists of a hthium-metal foil anode, a porous carbon cathode, a porous non-woven glass or polymeric separator between them, and an electrolyte containing thionyl chloride and a soluble salt, usually hthium tetrachloroaluminate. Thionyl chloride serves as both the cathode active material and the electrolytic solvent The carbon cathode serves as a catalytic surface for the reduction of thionyl chloride and as a repository for the insoluble products of the discharge reaction. 

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