Lithium chlorine cells

Fig. 8.9 Schematic diagram of a vertical experimental lithium-chlorine cell...

Nickel-zinc storage cells Nickel-hydrogen storage cells Chlorine-zince storage cells Sulfur-sodium storage cells Iron sulfide-lithium storage cells Zinc-air cells Iron-air storage cells... 

Polymer electrolytes are used in lithium ion rechargeable batteries. Pure polymer electrolyte systems include polyethylene oxide (PEO), polymethylene-polyethylene oxide (MPEG), or polyphosphazenes. Chlorinated PVC blended with a terpoly-mer comprising vinylidene chloride/acrylonitrile/methyl methacrylate can make a good polymer electrolyte. Rechargeable lithium ion cells use solid polymer electrolytes. Plasticized polymer electrolytes are safer than liquid electrolytes because of a reduced amount of volatiles and flammables. The polymer membrane can condnct lithinm ions. The polymer membrane acts as both the separator and electrolyte [7],... 

The Fuel Cell (or Electricity Producer). A fuel cell is shown schematically in Fig. 7.5. Instead of pushing the reactions at the electrodes to go against their spontaneous tendency, the fuel cell consumes chemicals (their fuels), and the overall result of the reactions at its two electrodes is the consequence of allowing the reaction in the cell to occur spontaneously. As can be seen from the figure, the electrons produced from the oxidation of the lithium fuel at the one electrode pass out of the cell and travel on through a load (which could be an electric motor) and then pass on to reduce chlorine to chloride at the second electrode (Fig. 7.5). 

The energy density of liquid cathode lithium cells can be further enhanced to over 500 Wh/kg (1000 Wh/dm3) by the use of halogen additives. BrCl, added to lithium-thionyl chloride cells, boosts the OCV to 3.9 V and prevents the formation of sulphur in the early stages of discharge. D-sized cells are manufactured, Addition of chlorine to lithium-sulphur yl chloride cells increases the energy density and improves the temperature-dependent electrical characteristics. 

It is estimated that under normal operating conditions not more than 5% of the lithium formed reacts in the cell. Probable reactions are (1) with air drawn into the cell as the chlorine is drawn off ( S), (2) with moisture from lithium chloride additions, (3) with chlorine (4)y and (4) with carbon from the anode (1),... 

Similar designs have been used in lithium chloride batteries, which operate at a temperature of 650°C. The cell has the form Li (liq.)/LiCl (liq.yClj (g), carbon.The two electrodes, the liquid lithium anode and the porous carbon anode in which the chlorine gas is fed imder pressure, are separated by a molten lithimn chloride electrolyte. The overall cell reaction is... 

Catalyst Research Corporation (USA) is a major manufacturer of lithium—iodine batteries used for pacemaker and other applications. The Catalyst Research Series 800 cells use the lithium envelope concept. The cell is constructed with a centrally located cathode current collector and a lithium envelope which surrounds and contains the iodine depolarizer material (Figure 24.14). This depolarizer material is corrosive to the stainless steel case and must be kept irxnn contacting the case for maximum cell life. A second barrier, formed from fluorocarbon plastics, surrounds the lithium envelope, insulates it from the case, and provides a second envelope for the containment of the depolarizer. The corrosive effect of iodine-containing depolarizer on stainless steel is lower than that of depolarizer made with more active halogens, such as bromine or chlorine. 

The next report on this type of experiment appeared recently [61, 62]. Geske and Maki recorded signals from chlorine-containing radical ions by oxidizing a 0.1-mole/liter solution of lithium perchlorate in acetonitrile at a platinum electrode in a special cell adapted so that the electrolysis could be carried out in the resonance cavity. Soon after this, EPR spectra showing complex hyperfine structure due to organic radical ions were recorded for the first time (nitrobenzene radical ions), using the same method [31]. 

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