The lithium anode in primary cells

Atomic weight Melting point Boiling point Density Heat of fusion Heat of vaporization Resistivity 

The reaction of lithium with the electrolyte to form a surface film significantly modifies its behaviour. On the one hand, the film confers chemical stability and useful shelf life on the system. On the other, it is responsible for greatly depressed exchange currents and the consequent phenomenon of voltage delay, as discussed in Chapter 3 in connection with magnesium aqueous batteries. It is convenient to discuss separately film formation with insoluble and with liquid and soluble cathode systems. 

In these cells, provided that the solubility of the cathode material is very low, the solvent itself is principally responsible for film formation although the anion of the salt is often also involved. Lithium was originally thought to react with propylene carbonate (PC) to form gaseous propene and lithium carbonate as follows  

On drawing current from a passivated lithium anode, polarization may be at first severe, but the voltage recovers fairly rapidly (Fig. 4.6). Initially, charge transfer at the anode is limited by lithium ion transport through a thin or imperfect section of the interfacial film. This process progressively 

Cells with liquid or soluble cathodic reagents 

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