  Redox-based nanoionic resistive memory cells (ReRAMs) are one of the most
promising emerging nano-devices for future information technology with
applications for memory, logic and neuromorphic computing. Recently, the
serendipitous discovery of the link between ReRAMs and memristors and
memristive devices has further intensified the research in this field. Here we
show on both a theoretical and an experimental level that nanoionic-type
memristive elements are inherently controlled by non-equilibrium states
resulting in a nanobattery. As a result the memristor theory must be extended
to fit the observed non zerocrossing I-V characteristics. The initial
electromotive force of the nanobattery depends on the chemistry and the
transport properties of the materials system but can also be introduced during
ReRAM cell operations. The emf has a strong impact on the dynamic behaviour of
nanoscale memories, and thus, its control is one of the key factors for future
device development and accurate modelling.
