title: Space charge storage in composites: thermodynamics.
abstract: Contacts of two phases, which allow for synergistic dissociative storage of a component in two space charge zones ("job-sharing storage"), are considered from the viewpoint of point defect thermodynamics. The respective relations between charge and component activity (chemical potential of the component) are derived, or - for more complex cases - the recipes for their derivation are given. These relations describe - according to different experimental conditions - the connection between mass storage and outer partial pressure or between mass storage and the cell voltage in a coulometric titration cell. They also reflect theoretical charge/discharge curves in battery cells when job-sharing storage predominates, and thus are also significant for supercapacitors. In addition to explicitly worked-out cases, it is pointed out how more general situations, such as simultaneous storage in bulk and in boundaries, specific adsorption or size effects, are to be treated.
authors.affiliation: Max Planck Institute for Solid State Research, Heisenbergstr.1, D-70569 Stuttgart, Germany. s.weiglein@fkf.mpg.de.
authors.forename: Chia-Chin
authors.identifier: http://orcid.org/0000-0001-7198-0964
authors.initials: CC
authors.lastname: Chen
authors.affiliation: Max Planck Institute for Solid State Research, Heisenbergstr.1, D-70569 Stuttgart, Germany. s.weiglein@fkf.mpg.de.
authors.forename: Joachim
authors.initials: J
authors.lastname: Maier