Patent attributes
Provided are electrochemical systems with electronically and ionically conductive layers that have electronic, mechanical and chemical properties useful for a variety of applications including electrochemical storage and conversion. State of the art electrochemical cells are made with electronically non-conductive separators between the opposite electrodes as the natural choice to prevent any electronic path between the opposite electrodes. Herein, electronically conductive layers are introduced between an electrode and the separator without producing any direct electronic path between the opposite electrodes. Embodiments provide structural, physical and electrostatic attributes useful for managing and controlling dendrite formation and for improving the cycle life and rate capability of electrochemical cells including silicon anode based batteries, air cathode based batteries, redox flow batteries, solid electrolyte based systems, fuel cells, flow batteries and semisolid batteries. Disclosed electronically and ionically conductive layers include multilayer, porous geometries supporting excellent ion transport properties, providing a barrier to prevent dendrite initiated mechanical failure, shorting or thermal runaway, or providing improved electrode conductivity and improved electric field uniformity. Disclosed electronically and ionically conductive layers between the separator and an electrode include metals, metal alloys, a carbon materials, semiconductors, electronically conductive polymers, electronically conductive ceramics and any combination of these.
