An apparatus and method for measuring the isoelectric pH for materials deposited on or otherwise affixed onto and in contact with an
electrode surface, and a method for utilizing the isoelectric pH to form nanometer thickness, self-assembled
layers on the material, are described. Forming such
layers utilizing information obtained about the isoelectric pH values of the substrate and the
coating is advantageous since the growth of the
coating is self-limiting because once the
surface charge has been neutralized there is no longer a driving force for the
solid electrolyte coating thickness to increase, and uniform coatings without pinhole defects will be produced because a local driving force for
assembly will exist if any bare
electrode material is exposed to the solution. The present self-
assembly procedure, when combined with electrodeposition, may be used to increase the coating thickness. Self-
assembly, with or without additional electrodeposition, allows intimate contact between the
anode,
electrolyte and
cathode which is required for successful application to
solid-state batteries, as an example.