The reduction of. electrodeposited P-lead dioxide to lead
sulphate in 5M sulphuric acid has been studied at the stationary
and RDE. Potential step and sweep experiments have been made and
a model for the discharge process of lead dioxide has been
proposed based on charge transfer and limited high field conduction.
T'he potentiostatic oxidations of lead sulphate overlying lead and
lead dioxide have been investigated.
The reduction behaviour of porous one-dimensional lead dioxide
electrodes have been examined and shown to be independant of
rotation speed in a large excess of 5M sulphuric acid. The reduction
peak was broadened by the porosity. This broadening was interpreted
in terms of the reaction being driven more deeply into the pore
structure as the front of the electrode becomes progressively more
resistive. The effect of different potential sweep rates on the
current response and effects of progressive redox cycles can be
fully explained on this model. The potentiostatic oxidation of
porous electrodes of lead dioxide containing lead sulphate has also
been investigated. The form of the current transient was found to
depend on the balance of lead sulphate and lead dioxide.
Investigations have been carried out on the above electrodes using
the techniques of scanning electron microscopy and alternating current.
Possible interpretations of the results are discussed. The influence of the solid/porous material interphase on the
electrode behaviour has been investigated for a variety of alloy
supports with special reference to the charge output on reduction,
ease of reoxidation and electrode support/porous phase adhesion.
The progress made in the understanding of some of the problems
associated with the lead acid cell has been discussed.
Doctoral Thesis. Submitted in partial fulfilment of the requirements for the award of Doctor of Philosophy of Loughborough University.